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The Regression-Discontinuity Design
The regression-discontinuity design. What a terrible name! In everyday language both parts of the term have connotations that are primarily negative. To most people "regression" implies a reversion backwards or a return to some earlier, more primitive state while "discontinuity" suggests an unnatural jump or shift in what might otherwise be a smoother, more continuous process. To a research methodologist, however, the term regression-discontinuity (hereafter labeled "RD") carries no such negative meaning. Instead, the RD design is seen as a useful method for determining whether a program or treatment is effective.
The label "RD design" actually refers to a set of design variations. In its simplest most traditional form, the RD design is a pretest-posttest program-comparison group strategy. The unique characteristic which sets RD designs apart from other pre-post group designs is the method by which research participants are assigned to conditions. In RD designs, participants are assigned to program or comparison groups solely on the basis of a cutoff score on a pre-program measure. Thus the RD design is distinguished from randomized experiments (or randomized clinical trials) and from other quasi-experimental strategies by its unique method of assignment. This cutoff criterion implies the major advantage of RD designs – they are appropriate when we wish to target a program or treatment to those who most need or deserve it. Thus, unlike its randomized or quasi-experimental alternatives, the RD design does not require us to assign potentially needy individuals to a no-program comparison group in order to evaluate the effectiveness of a program.
The RD design has not been used frequently in social research. The most common implementation has been in compensatory education evaluation where school children who obtain scores which fall below some predetermined cutoff value on an achievement test are assigned to remedial training designed to improve their performance. The low frequency of use may be attributable to several factors. Certainly, the design is a relative latecomer. Its first major field tests did not occur until the mid-1970s when it was incorporated into the nationwide evaluation system for compensatory education programs funded under Title I of the Elementary and Secondary Education Act (ESEA) of 1965. In many situations, the design has not been used because one or more key criteria were absent. For instance, RD designs force administrators to assign participants to conditions solely on the basis of quantitative indicators thereby often impalatably restricting the degree to which judgment, discretion or favoritism may be used. Perhaps the most telling reason for the lack of wider adoption of the RD design is that at first glance the design doesn't seem to make sense. In most research, we wish to have comparison groups that are equivalent to program groups on pre-program indicators so that post-program differences may be attributed to the program itself. But because of the cutoff criterion in RD designs, program and comparison groups are deliberately and maximally different on pre-program characteristics, an apparently insensible anomaly. An understanding of how the design actually works depends on at least a conceptual familiarity with regression analysis thereby making the strategy a difficult one to convey to nonstatistical audiences.
Despite its lack of use, the RD design has great potential for evaluation and program research. From a methodological point of view, inferences which are drawn from a well-implemented RD design are comparable in internal validity to conclusions from randomized experiments. Thus, the RD design is a strong competitor to randomized designs when causal hypotheses are being investigated. From an ethical perspective, RD designs are compatible with the goal of getting the program to those most in need. It is not necessary to deny the program from potentially deserving recipients simply for the sake of a scientific test. From an administrative viewpoint, the RD design is often directly usable with existing measurement efforts such as the regularly collected statistical information typical of most management information systems. The advantages of the RD design warrant greater educational efforts on the part of the methodological community to encourage its use where appropriate.
The Basic Design
The "basic" RD design is a pretest-posttest two group design. The term "pretest- posttest" implies that the same measure (or perhaps alternate forms of the same measure) is administered before and after some program or treatment. (In fact, the RD design does not require that the pre and post measures are the same.) The term "pretest" implies that the same measure is given twice while the term "pre-program" measure implies more broadly that before and after measures may be the same or different. It is assumed that a cutoff value on the pretest or pre-program measure is being used to assign persons or other units to the program. Two group versions of the RD design might imply either that some treatment or program is being contrasted with a no-program condition or that two alternative programs are being compared. The description of the basic design as a two group design implies that a single pretest cutoff score is used to assign participants to either the program or comparison group. The term "participants" refers to whatever unit is assigned. In many cases, participants are individuals, but they could be any definable units such as hospital wards, hospitals, counties, and so on. The term "program" will be used throughout to refer to any program, treatment or manipulation whose effects we wish to examine. In notational form, the basic RD design might be depicted as shown in the figure where:
- C indicates that groups are assigned by means of a cutoff score,
- an O stands for the administration of a measure to a group,
- an X depicts the implementation of a program,
- and each group is described on a single line (i.e., program group on top, control group on the bottom).
To make this initial presentation more concrete, we can imagine a hypothetical study where the interest is in examining the effect of a new treatment protocol for inpatients with a particular diagnosis. For simplicity, we can assume that we wish to try the new protocol on patients who are considered most ill and that for each patient we have a continuous quantitative indicator of health that is a composite rating which can take values from 1 to 100 where high scores indicate greater health. Furthermore, we can assume that a pretest cutoff score of 50 was (more or less arbitrarily) chosen as the assignment criterion or that all those scoring lower than 50 on the pretest are to be given the new treatment protocol while those with scores greater than or equal to 50 are given the standard treatment.
It is useful to begin by considering what the data might look like if we did not administer the treatment protocol but instead only measured all participants at two points in time. Figure 1 shows the hypothetical bivariate distribution for this situation. Each dot on the figure indicates a single person's pretest and posttest scores. The blue Xs to the left of the cutoff show the program cases. They are more severely ill on both the pretest and posttest. The green circles show the comparison group that is comparatively healthy on both measures. The vertical line at the pretest score of 50 indicates the cutoff point (although for Figure 1 we are assuming that no treatment has been given). The solid line through the bivariate distribution is the linear regression line. The distribution depicts a strong positive relationship between the pretest and posttest – in general, the more healthy a person is at the pretest, the more healthy they'll be on the posttest, and, the more severely ill a person is at the pretest, the more ill they'll be on the posttest.
Now we can consider what the outcome might look like if the new treatment protocol is administered and has a positive effect. For simplicity, we will assume that the treatment had a constant effect which raised each treated person's health score by ten points. This is portrayed in Figure 2.
Figure 2 is identical to Figure 1 except that all points to the left of the cutoff (i.e., the treatment group) have been raised by 10 points on the posttest. The dashed line in Figure 2 shows what we would expect the treated group's regression line to look like if the program had no effect (as was the case in Figure 1).
It is sometimes difficult to see the forest for the trees in these types of bivariate plots. So, let's remove the individual data points and look only at the regression lines. The plot of regression lines for the treatment effect case of Figure 2 is shown in Figure 3.
On the basis of Figure 3, we can now see how the RD design got its name - - a program effect is suggested when we observe a "jump" or discontinuity in the regression lines at the cutoff point. This is illustrated in Figure 4.
The Logic of the RD Design
The discussion above indicates what the key feature of the RD design is: assignment based on a cutoff value on a pre-program measure. The cutoff rule for the simple two-group case is essentially:
- all persons on one side of the cutoff are assigned to one group…
- all persons on the other side of the cutoff are assigned to the other
- need a continuous quantitative pre-program measure
Selection of the Cutoff. The choice of cutoff value is usually based on one of two factors. It can be made solely on the basis of the program resources that are available. For instance, if a program only has the capability of handling 25 persons and 70 people apply, one can choose a cutoff point that distinguishes the 25 most needy persons from the rest. Alternatively, the cutoff can be chosen on substantive grounds. If the pre-program assignment measure is an indication of severity of illness measured on a 1 to 7 scale and physicians or other experts believe that all patients scoring 5 or more are critical and fit well the criteria defined for program participants then a cutoff value of 5 may be used.
Interpretation of Results.. In order to interpret the results of an RD design, one must know the nature of the assignment variable, who received the program and the nature of the outcome measure. Without this information, there is no distinct outcome pattern which directly indicates whether an effect is positive or negative.
To illustrate this, we can construct a new hypothetical example of an RD design. Let us assume that a hospital administrator would like to improve the quality of patient care through the institution of an intensive quality of care training program for staff. Because of financial constraints, the program is too costly to implement for all employees and so instead it will be administered to the entire staff from specifically targeted units or wards which seem most in need of improving quality of care. Two general measures of quality of care are available. The first is an aggregate rating of quality of care based on observation and rating by an administrative staff member and will be labeled here the QOC rating. The second is the ratio of the number of recorded patient complaints relative to the number of patients in the unit over a fixed period of time and will be termed here the Complaint Ratio. In this scenario, the administrator could use either the QOC rating or Complaint Ratio as the basis for assigning units to receive the training. Similarly, the effects of the training could be measured on either variable. Figure 5 shows four outcomes of alternative RD implementations possible under this scenario.
Only the regression lines are shown in the figure. It is worth noting that even though all four outcomes have the same pattern of regression lines, they do not imply the same result. In Figures 5a and 5b, hospital units were assigned to training because they scored below some cutoff score on the QOC rating. In Figures 5c and 5d units were given training because they scored above the cutoff score value on the Complaint Ratio measure. In each figure, the dashed line indicates the regression line we would expect to find for the training group if the training had no effect. This dashed line represents the no-discontinuity projection of the comparison group regression line into the region of the program group pretest scores.
We can clearly see that even though the outcome regression lines are the same in all four groups, we would interpret the four graphs differently. Figure 5a depicts a positive effect because training raised the program group regression line on the QOC rating over what would have been expected. Figure 5b however shows a negative effect because the program raised training group scores on the Complaint Ratio indicating increased complaint rates. In Figure 5c we see a positive effect because the regression line has been lowered on the Complaint Ratio relative to what we would have expected. Finally, Figure 5d shows a negative effect where the training resulted in lower QOC ratings than we would expect otherwise. The point here is a simple one. A discontinuity in regression lines indicates a program effect in the RD design. But the discontinuity alone is not sufficient to tell us whether the effect is positive or negative. In order to make this determination, we need to know who received the program and how to interpret the direction of scale values on the outcome measures.
The Role of the Comparison Group in RD Designs. With this introductory discussion of the design in mind, we can now see what constitutes the benchmark for comparison in the RD design. In experimental or other quasi- experimental designs we either assume or try to provide evidence that the program and comparison groups are equivalent prior to the program so that post-program differences can be attributed to the manipulation. The RD design involves no such assumption. Instead, with RD designs we assume that in the absence of the program the pre-post relationship would be equivalent for the two groups. Thus, the strength of the RD design is dependent on two major factors. The first is the assumption that there is no spurious discontinuity in the pre-post relationship which happens to coincide with the cutoff point. The second factor concerns the degree to which we can know and correctly model the pre-post relationship and constitutes the major problem in the statistical analysis of the RD design which will be discussed below.
The Internal Validity of the RD Design. Internal validity refers to whether one can infer that the treatment or program being investigated caused a change in outcome indicators. Internal validity as conceived is not concerned with our ability to generalize but rather focuses on whether a causal relationship can be demonstrated for the immediate research context. Research designs which address causal questions are often compared on their relative ability to yield internally valid results.
In most causal hypothesis tests, the central inferential question is whether any observed outcome differences between groups are attributable to the program or instead to some other factor. In order to argue for the internal validity of an inference, the analyst must attempt to demonstrate that the program – and not some plausible alternative explanation – is responsible for the effect. In the literature on internal validity, these plausible alternative explanations or factors are often termed "threats" to internal validity. A number of typical threats to internal validity have been identified. For instance, in a one-group pre-post study a gain from pretest to posttest may be attributable to the program or to other plausible factors such as historical events occurring between pretest and posttest, or natural maturation over time.
Many threats can be ruled out with the inclusion of a control group. Assuming that the control group is equivalent to the program group prior to the study, the control group pre-post gain will provide evidence for the change which should be attributed to all factors other than the program. A different rate of gain in the program group provides evidence for the relative effect of the program itself. Thus, we consider randomized experimental designs to be strong in internal validity because of our confidence in the probabilistic pre-program equivalence between groups which results from random assignment and helps assure that the control group will provide a legitimate reflection of all non-program factors that might affect outcomes.
In designs that do not use random assignment, the central internal validity concern revolves around the possibility that groups may not be equivalent prior to the program. We use the term "selection bias" to refer to the case where pre-program differences between groups are responsible for post-program differences. Any non-program factor which is differentially present across groups can constitute a selection bias or a selection threat to internal validity.
In RD designs, because of the deliberate pre-program differences between groups, there are several selection threats to internal validity which might, at first glance, appear to be a problem. For instance, a selection-maturation threat implies that different rates of maturation between groups might explain outcome differences. For the sake of argument, let's consider a pre-post distribution with a linear relationship having a slope equal to two units. This implies that on the average a person with a given pretest score will have a posttest score two times as high. Clearly there is maturation in this situation, that is, people are getting consistently higher scores over time. If a person has a pretest score of 10 units, we would predict a posttest score of 20 for an absolute gain of 10. But, if a person has a pretest score of 50 we would predict a posttest score of 100 for an absolute gain of 50. Thus the second person naturally gains or matures more in absolute units (although the rate of gain relative to the pretest score is constant). Along these lines, in the RD design we expect that all participants may mature and that in absolute terms this maturation may be different for the two groups on average. Nevertheless, a program effect in the RD design is not indicated by a difference between the posttest averages of the groups, but rather by a change in the pre-post relationship at the cutoff point. In this example, although we expect different absolute levels of maturation, a single continuous regression line with a slope equal to 2 would describe these different maturational rates. More to the point, in order for selection-maturation to be a threat to internal validity in RD designs, it must induce a discontinuity in the pre-post relationship which happens to coincide with the cutoff point – an unlikely scenario in most studies.
Another selection threat to internal validity which might intuitively seem likely concerns the possibility of differential regression to the mean or a selection-regression threat. The phenomenon of regression to the mean arises when we asymmetrically sample groups from a distribution. On any subsequent measure the obtained sample group mean will be closer to the population mean for that measure (in standardized units) than the sample mean from the original distribution is to its population mean. In RD designs we deliberately create asymmetric samples and consequently expect regression towards the mean in both groups. In general we expect the low-scoring pretest group to evidence a relative gain on the posttest and the high-scoring pretest group to show a relative loss. As with selection-maturation, even though we expect to see differential regression to the mean this poses no problem for the internal validity of the RD design. We don't expect that regression to the mean will result in a discontinuity in the bivariate relationship coincidental with the cutoff point. In fact, the regression to the mean that will occur is expected to be continuous across the range of the pretest scores and is described by the regression line itself. (We should recall that the term "regression" was originally used by Galton to refer to the fact that a regression line describes regression to the mean.)
Although the RD design may initially seem susceptible to selection biases, it is not. The above discussion demonstrates that only factors that would naturally induce a discontinuity in the pre-post relationship could be considered threats to the internal validity of inferences from the RD design. In principle then the RD design is as strong in internal validity as its randomized experimental alternatives. In practice, however, the validity of the RD design depends directly on how well the analyst can model the true pre-post relationship, certainly a nontrivial statistical problem as is discussed in the statistical analysis of the regression-discontinuity design.
The RD Design and Accountability. It makes sense intuitively that the accountability of a program is largely dependent on the explicitness of the assignment or allocation of the program to recipients. Lawmakers and administrators need to recognize that programs are more evaluable and accountable when the allocation of the program is more public and verifiable. The three major pre-post designs – the Pre-Post Randomized Experiments, the RD Design, and the Nonequivalent Groups Design – are analogous to the three types of program allocation schemes which legislators or administrators might choose. Randomized experiments are analogous to the use of a lottery for allocating the program. RD designs can be considered explicit, accountable methods for assigning program recipients on the basis of need or merit. Nonequivalent group designs might be considered a type of political allocation because they enable the use of unverifiable, subjective or politically-motivated assignment. Most social programs are politically allocated. Even when programs are allocated primarily on the basis of need or merit, the regulatory agency usually reserves some discretionary capability in deciding who receives the program. Without debating the need for such discretion, it is clear that the methodological community should encourage administrators and legislators who wish their programs to be accountable to make explicit their criteria for program eligibility by either using probabilistically based lotteries or by relying on quantitative eligibility ratings and cutoff values as in the RD design. To the extent that legislators and administrators can be convinced to move toward more explicit assignment criteria, both the potential utility of the RD design and the accountability of the programs will be increased.
Ethics and the RD Design
The discussion above argues that the RD Design is strong in internal validity, certainly stronger than the Nonequivalent Groups Design, and perhaps as strong as the Randomized Experiments. But we know that the RD Designs are not as statistically powerful as the Randomized Experiments. That is, in order to achieve the same level of statistical accuracy, an RD Design needs as much as 2.75 times the participants as a randomized experiment. For instance, if a Randomized Experiment needs 100 participants to achieve a certain level of power, the RD design might need as many as 275.
So why would we ever use the RD Design instead of a randomized one? The real allure of the RD Design is that it allows us to assign the treatment or program to those who most need or deserve it. Thus, the real attractiveness of the design is ethical – we don't have to deny the program or treatment to participants who might need it as we do in randomized studies.


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[cnn-photo-caption image= http://i2.cdn.turner.com/cnn/2010/images/04/15/art.tthompson0415.gi.jpg caption ="Former Wisconsin Gov. Tommy Thompson has decided not to run for Senator."](CNN) - Former Wisconsin Gov. Tommy Thompson has decided against mounting a Senate bid, dealing a blow to Republicans who viewed him as the party's best chance to topple incumbent Democrat Russ Feingold.
"My family didn't want me to run," Thompson told the Milwaukee Journal Sentinel Thursday about his decision not run. The onetime presidential candidate announced his decision at a Tea Party rally outside the Wisconsin State Capitol.
"It's time for new voices and new faces," Thompson told the crowd, according to local television station WBAY.
Thompson, who was governor of Wisconsin for 14 years and served as health and human services secretary under former President George W. Bush, remains popular in his home state. Recent polls showed that Thompson was running neck and neck with Feingold in a hypothetical matchup.
Thompson's decision leaves the race for the GOP Senate nomination to businessman Terrence Wall and former State Commerce Secretary Dick Leinenkugel - neither of whom have high name recognition throughout the state.
Feingold, who is seeking his fourth term as senator, is sitting on $4 million in campaign cash as he awaits an opponent, according to his campaign.
UPDATE 4:48 p.m.:
The Feingold campaign put out a statement Thursday afternoon with Sen. Feingold's reaction:
"I'm disappointed that Secretary Thompson decided not to get in the ring. I'm sure there will now be talk about other candidates getting in this race, but it's my hope that the election can now be focused where it should be – on the issues important to the people of Wisconsin and who will be an independent voice for them in Washington, working hard to move our state forward."
He left our state in the worst shape ever, and we still haven't recovered from his "governing".
I respect that he listens to his family. Campaigns can be very traumatic to families.
"It's time for new voices and new faces," Thompson told the crowd, according to local television station WBAY.
The "Mad Tea Cup Party" are eating their own!!

subset: commoncrawl


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April 17th is Equal Pay Day in the United States. Equal Pay Day marks how far into 2012 women have to work to earn what men did in 2011. See this graph by the Atlantic for an exploration of the pay gap by area of expertise, and the National Women's Law Center's and the American Association of University Women's state-by-state fact sheets and rankings about the wage gap.
Women on average only earn 77 cents for every dollar a man earns. It's even more grim if you are a women who happens to not have white skin: African-American women earn only 62 cents and Hispanic women only 54 cents for every dollar that a white, non-Hispanic man earns. The Labor Council for Latin American Advancement and it's Trabajadoras Campaign can help if you feel you have experienced wage discrimination. Their informative report on the status of Latina workers in the US is available for download on their site.
In case you were wondering what the extra cost of being a vagina'd-American is, here's a rough estimate compiled by Jezebel. It doesn't include the cost of treating vagina-specific sexual health issues like bacterial vaginosis or PID which can be quite costly, but hey, nobody's perfect. Also chech out this chart explaining how much more women pay for health insurance by state, unfair right? Especially when you figure out that the average tax cut per millionaire in 2012 could support 551 people receiving family planning services. And just think, with the extra $431,360 you would earn over your lifetime if you were a penis'd-American, you could pay for SEVEN four-year college degrees, or 921 abortions.
Now, you might not need all those abortions if you had birth control. And if you had birth control you might be richer! Not only does birth control increase women's wages it also saves employers 15% to 17% more than they would have paid to "exclude birth-control coverage, both because other medical costs rise and because of lost productivity." If you can't afford birth control, just Google it.
Besides abortion and birth control issues, one important battlefront in the War on Women is the Republican Party's denial that the wage gap exists. In Wisconsin Governor Scott Walker, in a stunning display of inhumanity, repealed that state's equal pay law because, as Senator Glenn Grothman (R-Wis.) explained, "Money is more important for men."
Senator Grothman asserts that women are too busy caring for children to fret their pretty little heads over financial woes. His archaic assumption leaves most American women out of the equation, including single women, women without children, and all women-headed-households, including the 34% of women-headed-households that live below the poverty line. For many of these families there is no help coming from the government since they do not meet the strict criteria for Welfare.
At least one TV figure has asked the GOP why they don't pay women for mothering since being a mother is work. Being a mother is arguably the worst financial decision a woman can make in the US but many women like Selma James have worked for decades, fighting for women to be paid for the work they do in the home.
One of the best things you can do to put an end to wage discrimination, besides demanding a wage equal to what your male peers are making, is to demand your lawmakers enact the Equal Rights Amendment. As always your questions, comments, links or other addicting info are more than welcome and very much appreciated in the comments.
Go forth and equalize!
Related articles
- Nowhere Near Equal: Reflections on Equal Pay Day (youngwomenmisbehavin.com)
- Introducing: Equal Pay Day Ryan Gosling (thedailymuse.com)
- On Equal Pay Day, Step Up or Step Out of the Way (youngwomenmisbehavin.com)


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TicksAnna Murrell and Steve Barker
- Ixodidae (Hard ticks)
- Argasidae (Soft ticks)
- Nuttalliellidae
Ticks are blood-feeding parasites of reptiles, birds, mammals and even amphibians (one tick species only). Ticks are generally much larger than other mites; engorged female ticks of some species reach 30 mm in size (Evans, 1992). Ticks transmit more infectious agents than any other blood-feeding arthropods (Hoogstraal, 1985), including Borrelia burgdorgeri (Lyme disease), B. recurrentis (relapsing fever), Babesia spp. (tick fever), and Rickettsia connorii (boutenneuse fever). Other forms of pathogenesis attributed to ticks are anaemia (e.g. Hyalomma asiaticum females consume more than 8 ml of blood per tick; Sonenshine, 1991) as well as dermatosis and paralysis (Roberts and Janovy, 1996).
There are approximately 860 spp. in 22 genera and three families (Keirans, 1992; Keirans and Robbins, 1999). The Ixodidae and Argasidae are large and cosmopolitan families, whereas the Nuttalliellidae has one species which has only been found in South Africa and Tanzania (Evans, 1992). The main host of Nuttalliella namaqua is uncertain, as is the life cycle (Oliver, 1989). Most ixodid ticks have three hosts, one for each stage of the life cycle (larvae, nymph and adult), but in some species this has been reduced (one- or two-host ticks spend two or more life cycle stages on the same host individual) (Oliver, 1989). Ixodid ticks need several days to feed, and once the female is engorged she drops from the host to lay eggs (up to many thousand). Argasid ticks only feed intermittently and do not remain attached to their hosts. They may feed many times over their lifetime on a number of different hosts and will often lay only a few hundred eggs. Argasid ticks also have remarkable longevity and have been observed to live for many years and long periods of starvation (Sonenshine, 1991).
CharacteristicsAccording to Lehtinen (1991) the following characters are synapomorphic for the Ixodida:
- latigynial plates reduced;
- palpal tarsus reduced;
- hypostome projecting and sawlike.
Other prominent features of ticks are their large size, when compared to other mites, and Haller's organ, a complex sensory apparatus on tarsus 1 (the holothyridan mites have a homologous organ).
Discussion of Phylogenetic Relationships
The phylogenetic relationships of the three families of ticks, the Argasidae, Ixodidae and Nuttalliellidae, are unresolved. The monospecific Nuttalliellidae (Nuttalliella namaqua) has morphological features of both the Argasidae and Ixodidae (Keirans et al., 1976), so its relationship to them phylogenetically is unclear. Although molecular analyses of the phylogenetic relationships of the Argasidae and Ixodidae have been done (e.g. Black and Piesman, 1994; Black et al., 1997; Dobson and Barker, 1999), these studies did not include the Nuttalliellidae because few individuals of N. namaqua have ever been found (Roshdy et al., 1983), and they have not been available for molecular applications.
Black, W. C., Klompen, J. S. and Keirans, J. E. 1997. Phylogenetic relationships among tick subfamilies (Ixodida: Ixodidae: Argasidae) based on the 18S nuclear rDNA gene. Mol. Phylogenet. Evol., 7:129-44.
Black, W. C. and Piesman, J. 1994. Phylogeny of hard- and soft-tick taxa (Acari: Ixodida) based on mitochondrial 16S rDNA sequences. Proc. Natl. Acad. Sci. USA., 91:10034-8.
Dobson, S. J. and Barker, S. C. 1999. Phylogeny of the hard ticks (Ixodidae) inferred from 18S rRNA indicates the genus Aponomma is paraphyletic. Mol. Phylogenet. Evol., 11 (2): 288-295.
Evans, G. E. O. 1992. Principles of Acarology. CAB International, Wallingford, England.
Hoogstraal, H. 1985. Argasid and nuttalliellid ticks as parasites and vectors. Adv. Parasitol., 24:135-238.
Keirans, J. E., Clifford, C. M., Hoogstraal, H. and Easton, E. R. 1976. Discovery of Nuttalliella namaqua Bedford (Acarina: Ixodoidea: Nuttalliellidae) in Tanzania and re-description of the female based on scanning electron microscopy. Ann. Entomol. Soc. Am., 69:926-932.
Keirans, J. E. 1992. Systematics of the Ixodida (Argasidae, Ixodidae, Nuttalliellidae): An overview and some problems. Pp. 1-21 in B. H. Fivaz, T. N. Petney and I. G. Horak (ed.) Tick Vector Biology: Medical and Veterinary Aspects, Springer Verlag, Berlin.
Keirans, J. E. and Robbins, R. G. 1999. A world checklist of genera, subgenera, and species of ticks (Acari: Ixodida) published from 1973-1997. J. Vector Ecol., 24:115-129.
Lehtinen, P. T. 1991. Phylogeny and zoogeography of the Holothyrida. Pp101-113 in F. Dusbabek and V. Bukva (ed.) Modern Acarology, SPB Academic Publishing, The Hague.
Oliver, J. H. J. 1989. Biology and systematics of ticks (Acari: Ixodida). Ann. Rev. Ecol. Syst., 20:397-430.
Roberts, L. S. and Janovy, J. 1996. Foundations of parasitology. WCB Publishers, Dubuque, IA.
Roshdy, M. A., Hoogstraal, H., Banaja, A. A. and El Shoura, S. M. 1983. Nuttalliella namaqua (Ixodoidea: Nuttalliellidae): Spiracle structure and surface morphology. Z. Parasitenk., 69:817-821.
Sonenshine, D. E. 1991. Biology of ticks. Volume 1. Oxford University Press, New York.
Information on the Internet
About This Page
Anna Murrell
University of Queensland, Brisbane, Australia
Steve Barker
University of Queensland, Brisbane, Australia
Correspondence regarding this page should be directed to Anna Murrell at
Page copyright © 2001
All Rights Reserved.
- First online 20 December 2001
Citing this page:
Murrell, Anna and Steve Barker. 2001. Ixodida. Ticks. Version 20 December 2001. http://tolweb.org/Ixodida/2632/2001.12.20 in The Tree of Life Web Project, http://tolweb.org/


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1967 Ford Mustang - A Slam Dunk
Retired NBA baller George Lynch rides in style with his custom-built '67 Mustang
For many of us, retirement is a far off dream that we use to help us make it through the week at the office. However, for the fortunate few, retirement can come much earlier in life, where it can truly be appreciated. We'd all certainly like to retire at an age where we can still work out in the garage and enjoy our classic Mustang hobby right? One such lucky guy is George Lynch of Dallas, Texas. If you follow the NBA at all, his name might sound familiar to you. Fresh out of the University of North Carolina, where he led the Tar Heels to an NCAA title in 1993, Lynch joined the Los Angeles Lakers. For the next 12 years, he played for the Lakers, the 76ers, and the Hornets before retiring in 2005.
As a retirement present to himself, Lynch wanted to build an Eleanor Mustang (this was 2005 after all and the whole E-car thing was in full swing). Lynch reached out to Brian Dean at Ultimate Customs in Dulles, Virginia, for the build. Lynch actually played high school hoops with Brian's little brother at Flint Hill School outside of Washington, D.C., and got to know the Dean family well. Dean had already built a high-end Suburban and a Mercedes or two for Lynch over the years. Matter of fact, Lynch was Dean's first customer. Living in Dallas at the time, Lynch got an eyeful of the Eleanors being built by Unique Performance and wanted to build one as a retirement gift to himself. After some discussion, Dean talked Lynch out of the standard E-car build for something that looked more traditional.
"No way would I build him a car that someone could pull up to him at a light with the same thing," Dean tells us. Dean's plan called for a traditional, but smoothed look that had modern power and amenities, and drove and handled like a modern car too. "I was inspired by the recently built Fast Forward Fastback by Troy Trepanier—a very clean, 'hot-rod-style' muscle car. My vision was to build George a modern, classic driver," Dean explained. "Modern equipment, classic style and reliable driveability; it also had to have a wow factor about it everywhere you looked and not be a trailer queen," he added.
Lynch found a fastback on eBay that was represented as restored and a solid car. Unfortunately, when the fastback was delivered to Dean's shop, it was far from how it was represented. Dean pressed on with the project and disassembled the fastback and had it media blasted. What came back from the media blaster was far less of a Mustang than what the shop started with. While it might have been better to start with a Dynacorn body, you have to remember this was 2005 and there was no such thing. So out came the welders and nearly 30 panels were cut out and replaced on the fastback, some having to be hand formed by Dean's lead fabricator, Mike Gerber. Gerber was also responsible for the custom scoops and front valance, flush fitting the taillights, and filling the cowl vents.
By the time 2007 had rolled around, the body was in pristine shape with the body powdercoated and ready for final bodywork and paint. The underside was sprayed with Line-X bed liner material, and all suspension and drivetrain parts had been test fitted as well. 2008 was the beginning of the economy's downturn and Dean's shop was hit especially hard, causing Dean to close his doors. He didn't want to fail Lynch and vowed to finish the project on his own.
"I decided to see the project through and keep my commitment to the owner of the car, and not let the project die and give him back a non-completed car," Dean says. Dean called upon his pal Jason Huber at G-Force Design Concepts in Chambersburg, Pennsylvania, to handle the final bodywork, paint, and installation of the Roush 402IR engine and AOD transmission. A paint rendering was made by Nelson Michael of Hagerstown, Maryland, for Lynch to approve.
Dean took delivery of the painted and running fastback in the spring of 2010 for him to handle all of the fit and finish aspects, as well as the interior. Dean's good friend, Chris Torney, had just opened a custom audio and interior shop, CAS Design in Sterling, Virginia. Dean delivered the car to Torney to build a custom interior that reflected a modern feel, yet still had embodied the Mustang's classic styling. CAS Design fabricated a one-piece molded fiberglass headliner and covered the interior panels in a mix of Alcantara and leather. A custom console, speaker enclosures, and more were made for the car as well. At 6-feet, 8-inches, Lynch needed more leg room than the typical Mustang owner, so the seats were moved back 2 inches to accommodate Lynch.
Other interior upgrades include Nu-Relic power windows, and a JME gauge cluster with Auto Meter carbon-fiber gauges. Audio starts with a Kenwood double-DIN receiver at the front of the custom console sending Lynch's favorite tunes through a bevy of JL Audio amps to Focal speakers and JL subs. A Vintage Air Gen IV system keeps Lynch comfortable in the Texas heat. In April 2011, Dean wrapped the project and delivered the car to Lynch.
"This car was definitely the biggest project that I have ever taken on and took six years to complete. George was the most patient and understanding customer I have ever dealt with in my more than 15 years in the custom car business," Dean reflected. No matter how you look at the project, from Lynch to Dean and the other shops that helped Dean pull it all together, those involved certainly pulled off a slam-dunk!
"My vision was to build George a modern, classic driver," Dean explained. "Modern equipment, classic style and reliable driveability; it also had to have a wow factor about it everywhere you looked and not be a trailer queen."
The Details
George Lynch's '67 Mustang fastback
- Roush 402IR
- Dart block 9.5-inch deck height, four-bolt mains
- 402 cubic inches
- 4.00-inch bore
- 4.00-inch stroke
- 4340 forged billet steel crank
- 4340 billet steel H-beam rods
- 3⁄8-inch rod bolts
- Forged aluminum pistons
- 10:1 compression ratio
- Double roller timing chain
- Hydraulic roller camshaft
- Roush aluminum heads
- 2.02-inch intake, 1.60-inch exhaust valves
- Dual valvesprings
- Intake runner volume 185cc, fully CNC ported
- 1.6:1 roller rockers
- TWM fuel injection
- 50mm throttle bodies
- 36-lb/hr fuel injectors
- MSD billet distributor
- C. Cook Enterprises billet air stacks with mushroom air filters
- C. Cook Enterprises billet valve covers
- ACCEL DFI Gen7 engine management system
- Billet Specialties Tru-Trac serpentine drive system
- 140-amp Powermaster alternator
- Ford Racing water pump
- 500 hp, 500 lb-ft torque
- AOD four-speed automatic transmission by Roadmaster Transmission Service
- TCI Streetfighter converter, 2,400 stall
- Ford 9-inch rearend
- Richmond 3:50 gears
- Eaton Truetrac differential
- 31-spline axles
- Custom built headers 1¾-inch primary tubes, 2½-inch collectors
- Custom 2½-inch exhaust system
- MagnaFlow X-style pipe
- MagnaFlow mufflers
- Exhaust built by Mike Gerber
- Front: Fatman Fabrications PSM suspension kit, Ridetech air struts, Quickor 11⁄8-inch antisway bar
- Rear: Ridetech AirBar four-link with Shockwave air shocks, Quickor ¾-inch antisway bar
- AirRide Ridepro e3 controller, welded subframe connectors, custom x-brace
- Front: Baer Racing, 13-inch disc, four-piston calipers
- Rear: Baer Racing, 12-inch disc, four-piston calipers
- Front: Boyd Coddington Fury II polished, 18x8
- Rear: Boyd Coddington Fury II polished, 19x10
- Front: Pirelli P Zero Nero, P255/35R18
- Rear: Pirelli P Zero Nero, P295/30R19
Three-point shoulder belts, Nu-Relic power window conversion, custom one-piece fiberglass headliner wrapped in suede by CAS Design, leather Sparco Milano seats, seats moved back 2 inches, '06 Mustang shifter, custom JME Motorsports/Auto Meter carbon gauge cluster, Viper Alarm System, ididit tilt steering column, Vintage Air Gen IV A/C system, black Lokar pedals, custom center console by CAS Design, Auto Custom Carpet, Billet Specialties Vintec steering wheel, custom audio system designed by CAS Design featuring Kenwood V1000 Car Portal A/V controller, Kenwood L702 7-inch head unit, JL Audio 300/2 V2 Amplifier, JL Audio 500/1 V2 Amplifier, Focal 165KR2 6.5-inch component speakers
DuPont base/clear in Daytona Blue with Silver stripes, paint design by Nelson Michael, Hagerstown, Maryland; body and paint by G-Force Design Concepts, Chambersburg, Pennsylvania; custom steel lower front valance; handmade steel upper and lower quarter scoops by Mike Gerber; custom stainless steel mesh grille; smoothed cowl vents; smoothed and tucked bumpers; all emblems removed; lock cylinders removed; flushed LED Taillights; HID headlights with integrated LED turn signals; custom Honda S2000 power side mirrors by G-force Design Concepts; custom Euro-style gas cap; bumpers plated by Paul's Chroming, Evans City, Pennsylvania
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text: With a little luck of the Irish and some basic baking skills, these shimmering, shamrock-clad wafer paper cookies are a cinch! Take a look at some of our HOW-TO guides for tips and tricks for working with wafer paper. These little cookies are made with our Rectangle 3″ x 2″ Cookie Cutter, which fits these 1.5″ x 2.3″ designs perfectly. We added a little extra pizazz with a dusting of edible glitter (I mean, why not?!) and disco dust after the wafer paper dried. The best part is packaging for these adorable treats. New this year are the vintage St. Patrick's Day boxes below that fit these small rectangular cookies like a dream. Boxes are sold in sets of 6 varying designs that measure about 3.25″ x 2.25″ x 1″ each. A great gift idea or table favor to go along with a shepherd's pie and corned beef and cabbage dinner. Spread some green St. Patrick's Day cheer with homemade treats this year!


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NBC: Yep, Jay Leno took a 50 percent pay cut
Jay Leno definitely isn't joking — at least not when it comes to his salary.
The late-night host said that, in order to save the jobs of some of his staff members, he had taken a 50 percent pay cut as part of NBC's budget-slashing efforts last month, and the network has now confirmed Leno's claim.
In an interview with the Wall Street Journal, NBC entertainment chief Robert Greenblatt said the budget cuts were an effort to balance out money that was spent when Leno's show was briefly moved to prime time in 2009. It was later reinstated at 11:35 p.m. with the increased budget still in place.
"All we did was bring it back down to pre-prime time levels," Greenblatt told the Journal.
Report: Jay Leno takes pay cut as Tonight Show lays off 20 staff members
After the decrease, Leno's salary is about $15 million, the paper reports. As part of the negotiation, Leno's contract was also extended for two years, until May 2014.
As part of the budget cuts, NBC laid off 20 workers from the Tonight Show staff and reduced the show's $100 million annual budget by about 20 percent, Greenblatt said.
View original NBC Confirms Jay Leno's 50 Percent Pay Cut at TVGuide.com


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?About Game?*Exciting 3D action game!
*Stickman hero with powerful weapon arsenal.
*Special tricks with suit upgrades.
*Tons of enemies and fierce battles!
As evil clones invaded the town the true hero comes to help the citizen.
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Survive the epic battles and try to complete all the tasks.
Drive over your foes on cars, bikes or even tanks. You are the ultimate guard now so don't screw up!
Find secrets hidden on a large map.
Collect rewards for destroying your enemies and completing tasks, you can use it to buy best weapons in shop.
Hit hard and stick your line to the end.
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Click here to download Apk Mod Version – Drive Link
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Mommy Rope Game Apk Mod About this game Money:
Play Mommy Rope Game and enjoy the first-rate, smooth animations as heroes swing freely through the Gangster Crime city like never before. Mommy Rope Game how to play: Mommy Rope Game fly in the air using a rope at every point
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Mommy Rope Game fly in the air using a rope at every point
– Mommy Rope fight as a savor of your futuristic city not for yourself in a battle zone
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Mommy Rope Game gameplay Apk Mod:
– Mommy Rope fighting in the gangster crime city with cool music & sounds
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Flying Mommy Rope heroes are fighting in your support, you are everyone's hope and they are calling you my unique Mommy rope hero, show some super villain stealthy action for the survival of your futuristic grand city and make it secure.
DOWNLOAD Links:
Click here to download Apk Mod Version – Drive Link
Click here to download Apk Mod Version – Mega Nz
Click here to download Apk Mod Version – Go File
Data safety
Safety starts with understanding how developers collect and share your data. Data privacy and security practices may vary based on your use, region, and age. The developer provided this information and may update it over time.
Ratings and reviews
For us, enthusiasts, the love for games never changes. And to keep that love burning, we created this category to store the best MOD APK, Paid APK & Original APK games, as a premise to build a "so deep" playground for gamers. When participating in this journey, you will discover a new game world, a new land that you have never known. There are countless attractive, unique, and worth-playing titles shared every day. And a part of them are MOD APK games that serve the growing needs of many players. Especially we don't charge anything!
DOWNLOAD Links:
Click here to download Apk Mod Version – Drive Link
Click here to download Apk Mod Version – Mega Nz
Click here to download Apk Mod Version – Go File
Never mind the Play Protect warning!
As you know, MOD means editing APK files. As a result, the MOD APK files will not match the version available on the Google Play Store.
That's why Play Protect now warns you every time you want to install MOD APK.
How to choose the right version you want?
Choose the version that has the APK or APKs or XAPK icon only if you want to download the original.
Choose the version that has the MODicon if you want to download the MOD version.
How to install?
Each version has a different installation method. So on the download page of each version, we have specific installation instructions.
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Just wait a few seconds and the download button will appear.
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The server we use is a high quality, dedicated type that allows distribution of huge volumes of files to all users. Therefore, we are confident that the download speed of Apklink.Org is not inferior to any other storage system.
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The description is not correct with the downloaded file
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LPKF Laser & Electronics has announced it will exhibit at the 2013 Design West Exposition, which takes place April 23-25 at the McEnery Convention Center in San Jose, CA. From booth 1646, LPKF will demonstrate its line of in-house rapid PCB prototyping equipment by creating boards on its top of the line PCB milling machine, the ProtoMat S103.
The ProtoMat S103 is a benchtop PCB milling machine noted for its high accuracy. It creates PCBs by milling away unwanted copper from substrates, leaving only the desired circuit traces behind. Its standard set of features includes a pneumatic air bearing foot ideal for working with sensitive materials as well as the fiducial recognition camera which automates board alignment.
Throughout the two day exposition LPKF senior sales associate Rory Grondin will be producing PCBs on the ProtoMat S103, displaying the system's ease of use and quick turnaround capabilities.
Stop by booth 1646 at Design West to see the ProtoMat S103 in action. Or, for more information on how in-house PCB prototyping saves time and money over its alternatives, visit www.lpkfusa.com/pcb/.


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Jason Siska is currently a student teacher at Prairie Middle School in Barrington, Illinois, and also coaches gymnastics for middle and elementary school boys. He previously worked as a nude model for the Illinois State University Art Department, a carpenter/construction worker and after-school supervisor for Glenn Elementary School. He studied history and Spanish for four years at Illinois State University.
Born and raised in St. John, U.S. Virgin Islands, Siska moved to the "gold coast" of Chicago for five years before moving to the Barrington area for eight years. He then moved to Normal, Illinois for college.
Siska's hobbies include frisbee, rock-climbing, soccer and sailing. He describes himself as spontaneous, liberal and inquisitive. He is most proud of traveling alone for a summer in Central America and volunteering his services in Costa Rica and then backpacking through Columbia and the Lost City. He believes his abilities to rock-climb, fish, hunt, camp, cook, fire-tend, swim, boat and being a great masseuse will help him go far on SURVIVOR. He is also a certified PADI scuba diver.
Siska is currently single and lives in Fox River Grove, Illinois, with his Himalayan cats, Baby and Little Girl, along with his corn snake, Copper. His birth date is March 4, 1985.


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Some level of smartphone connectivity is standard on nearly every new car, but Toyota appears to be the first to implement the Car Connectivity Consortium's MirrorLink protocol in their iQ later this year. Besides playing music and making calls through the vehicle's infotainment system, the display on the connected smartphone will be mirrored on the iQ's larger seven inch touchscreen, making it easier to navigate the UI while driving.
Users with Nokia handsets will be able to connect to the Touch Life system using the Nokia Car Mode app available from their app store for devices running Symbian Belle. While the car is in motion the app provides a simplified version of the phone's UI, making it easier for a driver to place or take calls and operate the navigation and multimedia functions. But when the car is stationary, the Touch Life system then provides access to all of the phone's functionality, including the ability to use shortcut gestures on the larger touchscreen.
iPhone users running iOS 4 or later will have to download the Application Launcher app to connect their handsets to the the system. Which then provides remote access to navigation apps, internet radio and even social media like Facebook and Twitter. In both situations a set of steering wheel based controls also provide a safer way for drivers to control music playback and make calls, without taking their eyes off the road. But since the press release is only showing up on Toyota's European site, it's not known when the system will start showing up in North American vehicles. [Toyota via Engadget]


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With President Obama's sights set on his re-election, some decisions must be made about how the campaign can re-energize his base.
One segment, the gay community and their allies, has been frustrated with Obama and his "evolving" (at a snail's pace) stance on marriage equality. While the administration made good on its campaign promise on important issues such as the repeal of "Don't ask, don't tell," failing to support full marriage rights for gay couples is still a sticking point.
Since the economy is the most important issue of this election cycle, wedge issues such as gay rights may take a backseat to jobs. But the public's view of marriage equality may not actually have the negative impact that the Obama administration fears. Public opinion on the issue is heavily in favor of equal rights for gay citizens and could give Obama the political cover necessary to come out publicly in support of marriage equality.
If President Obama expressed support for marriage equality before the 2012 elections, there would be both benefits and risks. He would surely excite some of his supporters, especially those who feel that he too often shies away from bold stances in favor of measured pragmatism and common ground. On the other hand, some voters who support Obama but still oppose marriage equality may abandon the president over this issue. That leaves the president with two choices: Endorse marriage equality now or wait and play it safe until he is re-elected.
There are recent signs that the administration's position is evolving. Just last month, Secretary of Housing and Urban Development Shaun Donovan came out in support of marriage equality. In an interview with Metro Weekly, Donovan said that he "absolutely" endorsed same-sex marriage.
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Then there was the monumental speech by Secretary of State Hillary Clinton in which she stated emphatically that "gay rights are human rights, and human rights are gay rights" — a line that surely got preapproval from the White House, which knew that such a speech would make headlines worldwide. It seems that President Obama's administration is signaling that his personal evolution just might be complete, but the question is, will he admit it before November?
There is a long-held belief that Obama is a closeted supporter of marriage equality. Legend has it that when running for the Illinois Senate in 1996, he filled out a survey for a local newspaper indicating his support for gay rights and marriage. In the survey, Obama's typed responses said, "I favor legalizing same-sex marriages and would fight efforts to prohibit such marriages."
But by 1998, Obama had a somewhat different take on the issue. In another questionnaire, he indicated "undecided" in response to a question about whether Illinois should legalize same-sex marriage. A peculiar change in position, but probably a politically calculated one.
By 2008, presidential candidate Obama had come out in support only of civil unions (pdf) and not marriage. Perhaps the environment in 2008 didn't allow Obama to announce his stance publicly, but maybe 2012 will be different. One of the earliest signs that Obama was rethinking the issue came in 2009 when the administration announced that it was no longer defending the Defense of Marriage Act in court, saying that it considered the law unconstitutional.
But one group is certainly a factor in the administration's decision about whether to support marriage equality: socially conservative African Americans. They may not jump for joy if President Obama grants equal marriage rights to gay couples. It is important to note, however, that polling immediately after the administration's shift on DOMA revealed that the decision didn't affect Obama's support from socially conservative blacks.
President Obama likes to quote Martin Luther King's famous observation "The arc of the moral universe is long, but it bends towards justice." It appears that perhaps Obama, after a long evolutionary process, is finally ready to bend in the direction of equality and full marriage rights for all people.
Zerlina Maxwell is a political analyst and staff writer for Loop21.com, where she writes about national politics, candidates and specific policy and culture issues. She writes frequently about domestic violence, sexual assault, victim blaming and gender inequality. Follow her on Twitter.


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What is rapid innovation?
Innovation in large companies is a challenge. But speeding time to market is key to winning in innovation economy, so fast innovation is a necessity.
We have talked about the "Rapid innovation" model, creating an external entity dedicated to fast innovation:
- flexible, agile, open to new opportunities picked out from the innovation market, driven by "creative tension", it has strong assets to create and develop new products and associated leadership platform;
- in the same time, it maintains coordination with the core company (forging persistent connections between innovators and mainstream operations, and cultivating communication and collaboration skills) and alignement with core co innovation strategy, with a view to engage core co in the targeted innovation following "a line of least resistance".
Osman Can Ozcanli speaks about "in vitro method" designed for large company, a quite similar approach to "Rapid innovation": assuming that "innovation is the task of creative and risk taking individuals and small teams", "in vitro method" consists in finding these kinds of people, and letting them free in a flexible framework that I find very compelling:
- "Tell them you want them to innovate, give them a budget and some direction to work with, and let them experiment.
- Help them select a product concept that is in line with your family of products.
- Don't get in their way, just finance them.
- Let them own the vision for their product, but give them deadlines.
- Let them start their own company, hold their hands just a little.
- Let them produce and start selling when the time is right.
- If you want, draft an agreement that lets you buy their company for whatever its value if it all becomes successful later on."
Osman believes that "this innovation team will not only create an innovative product, but in about five years, they will create a brand and it will be a true brand that represents their passion behind the product." What's the risk? "If it fails, it is their failure. You just lost money. But If they make it, buy the company! The only risk was in financing their prototype – which believe me – ended up much cheaper than if you had paid your own engineers to do it. "
What is Open innovation?
This brings us one step closer to Open innovation. Open innovation as Henry Chesbrough puts it is "a process that starts with looking outside the organisation as you think about things to do inside. It is about "using other people's wheels" to get you moving", and breaking boundaries to look for innovation in the outside world.
Started in 2002, Open innovation has gone through three significant phases:
- collecting from outside and bringing external ideas into a company's own innovation process; this approach has some comunalities with Futures thinking framework: asking the question, scanning the world, mapping the possibilities, and asking the next question;
- developing new business out of collaboration involving companies making their unused ideas and technologies available to others, or sharing their recipe in their industry, finding a path in between collaboration and competition;
- creating new business models arising from opening up the process, opening the doors to cocreation, and customer communities driving a business.
Open innovation has been adopted by Procter & Gamble (P&G) in its innovation strategy since 2002, building the Connect and Develop model. I've met more recently with two other large companies, EDF and Veolia (French huge utilities), which have build their own approach, deriving the Open innovation model.
How does Open innovation work?
Let's go through 3 major innovation steps , Create, Develop, and Engage, and see what we learn from these experiences, and how it matches with "Rapid innovation" approach.
1. Create
- As explained in HBR "P&G, new innovation model" by Larry Huston et Nabil Sakka, VP innovation and senior VP R&D at P&G, it's in 2002, following a brainstorming about Pringles requiring new process, that "P&G, instead of investing on developing a workable process, created a technology brief defining the problems it needed to solve, and circulated it throughout its global networks of individuals and institutions to discover if anyone in the world had a readymade solution". They happened to find in an Italian bakery an adaptable method that solved its problem. "This innovation has helped the North America Pringles business achieve double-digit growth over the past two years." P&G knew best innovations had come from connecting ideas across internal businesses, and that external connections could produce highly profitable innovations, too. Accordingly, newly appointed CEO, A.G. Lafley made it P&G goal to "acquire 50% of our innovations outside the company". "Connect and Develop program, driven by the top leaders in the organization, was set up to find good ideas and bring them in to enhance and capitalize on internal capabilities". "P&G taps closed proprietary networks (70 technology entrepreneurs based around the world) and open networks (NineSigma, InnoCentive, YourEncore, Yet2.com). Using these networks, P&G look for ideas in government and private labs, as well as academic and other research institutions; P&G tap suppliers, retailers, competitors, development and trade partners, VC firms, and individual entrepreneurs." P&G met Lafley goal four years later and the share is now about 60 per cent.
- EDF Business Innovation was created in 2001 by Sebastien Jumel at EDF with a view to incubate and accelerate innovation, being a kind of missing link between R&D and market, a powerful R&D at EDF and a progressively deregulated market. EDF Business Innovation belongs to the Corporate Venture approach. It focused on recognizing, identifying innovations from outside, completing selection based on explicit criteria (intrinsec value and strategic synergy), finding innovations unknown from the R&D, and complementing internal know-how. Setting-up innovation networks in the Silicon Valley, among start-up and VCs to address innovation market was the sinews of war. EDF Business Innovation was composed of 20 people (representatives from EDF business lines, researchers, business developers) and has been part of Strategy & R&D Division, then Development division: . It has achieved 20 investments in 4 years time between 2001 and 2005.
- Veolia initiated the Innovation Accelerator program in 2010 in the context of abundant clean tech market. It built a platform to settle partnerships with clean tech start-up, harvest developments, enhance market & technology intelligence, and develop innovation speed to protect market share and profitability. It is based on the belief that "It is not the strongest who will survive, but those who can most easily adapt". Innovation Accelerator program targets to complete 4 successful partnerships in one year. Handled by Marie-Anne Brodschii and Robert Bozza, it is part of Veolia Environement Research & Innovation division, and is composed of 10 people.
2. Develop
- Following a screening process that involves busines line (see below : "Engagement"), P&G external business development (EBD) group contacts the product's manufacturer and begins negotiating licensing, collaboration, or other deal structures. Some arrangements both license to and license from the same company. "At this point, the product found on the outside has entered a development pipeline similar in many ways to that for any product developed in-house." This proved to work well with large companies, but part of P&G's challenge is now to learn how to work better with small and medium-sized companies, and entrepreneurs. Jeff Weedman, head of the 2010 Connect & Develop programme, says: "It's normal for new partners to have a concern that they will be overwhelmed" and that "some small entrepreneurs don't have the patience to work through" P&G's exhaustive procedures.
- EDF had created "Ease energie program" to work more closely with start-up: it consisted in exchanging engineers resources against capital share. EDF engineers had a very rewarding experience, understanding the start-up engine to facilitate further integration of the technology within EDF. Coming back to day to day work at EDF was not always easy.
- Veolia completes pilot projects, enabling start-up to test their innovation in the field; agreements are drafted between partner to ease cooperation, Veolia calls it "points de confort".
3. Engage
- For Connect and Develop to work, P&G realized, "it was crucial to know exactly what it was looking for, or where to play". They would seek ideas that had some degree of success already, and directed their surveillance to three environments: top ten consumer needs, adjacencies (new products or concepts that can help take advantage of existing brand equity), technology game boards (technology acquisition move in one area affecting products in other categories). We see all this preparation work, completed hand in hand with the core co and business units leaders, as a most efficient way to ensure engagement on the innovations brought back from outside. Starting from logging the external product into online "eureka catalog", screening process rapidly involves the business line who will "assess its alignment with the goals of the business, gauge the product's business potential and subject it to a battery of practical questions–such as whether P&G has the technical infrastructure needed to develop the product– meant to identify any showstopping impediments to development." P&G deeply pushed its culture, "telling its R&D staff that they should start by finding out whether relatedwork had been done elsewhere in the company, then if an external source–a partner or supplier, for instance – had a solution, before considering inventing a solution from scratch". P&G is now adapting its goal: "Instead of just focusing on the number [of external partnerships], let's focus on the value we can create. When we get those really, really big ideas, we want to scale them more quickly across the company and use them in more places across the company." says Bruce Brown, P&G's chief technology officer.
- EDF Business Innovation had defined 4 stragic business domains, associated with 4 sponsors to prepare managers buy-in. Axes for innovation were set up upstream, and a monthly innovation portfolio review was handled. EDF Business Innovation team was able to inolve EDF buyers and specialists on a specific topic. Engagement can be long and inconsistancy may happen in large companies: one has to buy some time to create porosity between innovation and mainstream operations; also "the more autonomous and fastest you are, the less chance you have to reintegrate smoothly innovation into core co business lines". Therefore, EDF Business Innovation had learned to build networks of allies and sometimes to move in concentric circles, finding bit by bit new allies in the hierarchy chart.
- External technologies are further integrated into Veolia service portfolio through commercial deals, so that Veolia and its partner are able to win together some new markets thanks to enriched service portfolio and Veolia extensive sales forces; to facilitate engagement, Veolia accelarator program works internally on collecting needs, interviewing business unit and program leaders, and setting-up roll-out priorities; it involves business units at the primary stage of clean-tech assessement. In the course of this process, Veolia accelerator program has built a map of internal innovation skills, a list of influencers, a marketing intelligence through a network of market researchers and worked on understanding resistance and getting support. Because research is quite decentralized at Veolia, these connections lead also to discovering unknown internal innovations!
In what ways is Open innovation an approach for fast innovation?
Open innovation meets "Rapid innovation" model in the Creation phase, in the sense that it feeds creation stage with external ideas, selected from an innovation market. "Creation tension", one of the three pillars of "rapid innovation" model can be leveraged in an open innovation approach, notably in the Diversity, Focus (fast iterative prototyping, short cycle), Leadership (narrow scope, metaphor & belief) dimensions.
Development stage can be faster as well if handled by the small external partner, or, because external process is already operational, products often move more quickly from concept to market.
But Engagement still remains the most difficult part as in the "Rapid innovation" model. It is all the more painful here that innovation come from the outside market: achieving buy-in from the core co is not easy, fear will drive rejection, and has to be anticipated from the start as in the P&G methodology.
The main lever is: prepare acceptance, create necessity for change.
Speaking of speed, what actually deeply changes in the Open innovation approach is the impact on growth following market initial penetration: the Geoffrey Moore crossing of the chasm, at a global scale. It brings the ability to deliver the kind of rapid growth and scale that would have taken a smaller company years or decades to attain on its own": "When we go global, you will go global. And it will be very quick" claims Jeff Weedman, head of the Connect & Develop programme at P&G.


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Death of Goldsmith's mother.-Biography of Parnell.--Agreement with Davies for the History of Rome.-Life of Bolingbroke.-The haunch of venison.
On his return to England, Goldsmith received the melancholy tidings of the death of his mother. Notwithstanding the fame as an author to which he had attained, she seems to have been disappointed in her early expectations from him. Like others of his family, she had been more vexed by his early follies than pleased by his proofs of genius; and in subsequent years, when he had risen to fame and to intercourse with the great, had been annoyed at the ignorance of the world and want of management, which prevented him from pushing his fortune. He had always, however, been an affectionate son, and in the latter years of her life, when she had become blind, contributed from his precarious resources to prevent her from feeling want.
He now resumed the labors of the pen, which his recent excursion to Paris rendered doubly necessary. We should have mentioned a Life of Parnell, published by him shortly after the Deserted Village. It was, as usual, a piece of job-work, hastily got up for pocket-money. Johnson spoke slightingly of it, and the author, himself, thought proper to apologize for its meagerness; yet, in so doing, used a simile, which for beauty of imagery and
felicity of language, is enough of itself to stamp a value upon
the essay.
"Such," says he, "is the very unpoetical detail of the life of a poet. Some dates and some few facts, scarcely more interesting than those that make the ornaments of a country tombstone. are all that remain of one whose labors now begin to excite universal curiosity. A poet, while living, is seldom an object sufficiently great to attract much attention; his real merits are known but to a few, and these are generally sparing in their praises. When his fame is increased by time, it is then too late to investigate the peculiarities of his disposition; the dews of morning are past, and we vainly try to continue the chase by the meridian splendor."
He now entered into an agreement with Davies, to prepare an abridgment in one volume duodecimo, of his History of Rome; but first to write a work for which there was a more immediate demand. Davies was about to republish Lord Bolingbroke's Dissertation on Parties, which he conceived would be exceedingly applicable to the affairs of the day, and make a probable hit during the existing state of violent political excitement; to give it still greater effect and currency he engaged Goldsmith to introduce it with a prefatory life of Lord Bolingbroke.
About this time Goldsmith's friend and countryman, Lord Clare, was in great affliction, caused by the death of his only son, Colonel Nugent, and stood in need of the sympathies of a kind-hearted friend. At his request, therefore, Goldsmith paid him a visit at his seat of Gosfield, taking his tasks with him. Davies was in a worry lest Gosfield Park should prove a Capua to the poet, and the time be lost. "Dr. Goldsmith," writes he to a friend, "has gone with Lord Clare into the country,
and I am plagued to get the proofs from him of the Life of Lord Bolingbroke." The proofs, however, were furnished in time for the publication of the work in December. The Biography,. though written during a time of political turmoil, and introducing a work intended to be thrown into the arena of politics, maintained that freedom from party prejudice observable in all the writings of Goldsmith. It was a selection of facts, drawn from many unreadable sources, and arranged into a clear, flowing narrative, illustrative of the career and character of one, who, as he intimates, "seemed formed by nature to take delight in struggling with opposition; whose most agreeable hours were passed in storms of his own creating; whose life was spent in a continual conflict of politics, and as if that was too short for the combat, has left his memory as a subject of lasting contention." The sum received by the author for this memoir, is supposed, from circumstances, to have been forty pounds.
Goldsmith did not find the residence among the great unattended with mortifications. He had now become accustomed to be regarded in London as a literary lion, and was annoyed, at what he considered a slight, on the part of Lord Camden. He complained of it on his return to town at a party of his friends. "I met him," said he, "at Lord Clare's house in the country; and he took no more notice of me than if I had been an ordinary man." "The company," says Boswell, "laughed heartily at this piece of 'diverting simplicity.'" And foremost among the laughers was doubtless the rattle-pated Boswell. Johnson, however, stepped forward, as usual, to defend the poet, whom he would allow no one to assail but himself; perhaps in the present instance he thought the dignity of literature itself involved in the question. "Nay, gentlemen," roared he, "Dr. Goldsmith is in
the right. A nobleman ought to have made up to such a man as Goldsmith, and I think it is much against Lord Camden that •he neglected him."
After Goldsmith's return to town he received from Lord Clare a present of game, which he has celebrated and perpetuated in his amusing verses entitled the "Haunch of Venison." Some of the lines pleasantly set forth the embarrassment caused by the appearance of such an aristocratic delicacy in the humble kitchen of a poet, accustomed to look up to mutton as a treat:
"Thanks, my lord, for your venison; for finer or fatter
The haunch was a picture for painters to study,
The fat was so white, and the lean was so ruddy;
Though my stomach was sharp, I could scarce help regretting,
To spoil such a delicate picture by eating:
I had thought in my chambers to place it in view,
To be shown to my friends as a piece of virtu;
But hang it-to poets, who seldom can eat,
Such dainties to them, their health it might hurt;
We have an amusing anecdote of one of Goldsmith's blunders which took place on a subsequent visit to Lord Clare's, when that nobleman was residing in Bath.
Lord Clare and the Duke of Northumberland had houses
next to each other, of similar architecture. Returning home one morning from an early walk, Goldsmith, in one of his frequent fits of absence, mistook the house, and walked up into the duke's dining-room, where he and the duchess were about to sit down to breakfast. Goldsmith, still supposing himself in the house of Lord Clare, and that they were visitors, made them an easy salutation, being acquainted with them, and threw himself on a sofa in the lounging manner of a man perfectly at home. The duke and duchess soon perceived his mistake, and, while they smiled internally, endeavored, with the considerateness of well-bred people, to prevent any awkward embarrassment. They accordingly chatted sociably with him about matters in Bath, until, breakfast being served, they invited him to partake. The truth at once flashed upon poor heedless Goldsmith; he started up from his free-and-easy position, made a confused apology for his blunder, and would have retired perfectly disconcerted, had not the duke and duchess treated the whole as a lucky occurrence to throw him in their way, and exacted a promise from him to dine with them.
This may be hung up as a companion-piece to his blunder on his first visit to Northumberland House.


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Mustard-Tarragon-Crusted Ham with Pineapple Salsa
Using a precooked ham makes this recipe easy to prepare. Just add some spices and mix up the salsa, and you'll have a delicious main dish for your meal.
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- Yields:
- 16
- Total Time:
- 2 hrs 30 mins
- c. loosely packed fresh tarragon leaves
- 1/4 c. Dijon mustard with seeds
- 1/4 c. loosely packed fresh parsley leaves
- 2 clove garlic
- pepper
- 1 fully cooked, spiral-sliced, smoked bone-in half ham
- 1 medium ripe pineapple
- 2 tbsp. fresh lime juice
- 1 green onion
- Step 1Preheat oven to 325 degrees F. Place 1 tablespoon chopped tarragon in medium bowl for salsa; set aside. In small bowl, combine remaining tarragon, Dijon, parsley, garlic, and 1/2 teaspoon freshly ground black pepper.
- Step 2Place ham on rack in large roasting pan (17" by 11 1/2"). Pat ham dry with paper towels. Rub Dijon mixture on skin sides of ham, pressing to adhere. Cover pan tightly with foil. Bake 2 hours or until meat thermometer inserted in thickest part of ham (not touching bone) reaches 140 degrees F.
- Step 3Meanwhile, make Pineapple Salsa: Cut crown and stem ends from pineapple; cut off rind. Slice pineapple lengthwise into quarters; remove and discard core from each quarter. Cut each quarter into 1/2-inch chunks. You will need 4 cups pineapple chunks; cover and refrigerate any additional pineapple for another use. Add pineapple to bowl with tarragon, and stir in lime juice and green onion. Makes about 4 cups salsa. Cover and refrigerate until ham is ready. Serve Pineapple Salsa with ham.
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Dry those tears, home cooks. There is now an onion that won't make you look like you've been sobbing all day.
Time reports that Asda, a British supermarket chain, is now selling a sweet red onion that doesn't wreak havoc on your tear ducts. The onions have lower pungency levels, which means they have a milder flavor and won't give you dreaded "onion breath" after eating them.
RELATED: The Tear-Free Way To Cut An Onion
More From Woman's Day
Farmer Alastair Findlay took more than 20 years and evaluated thousands of bulbs to come up with the perfect, tear-free onion. It's the first red onion ever to be grown in the U.K., and more than 400 tons will arrive in Asda stores this season.
RELATED: The Best Ways To Choose, Store And Use 5 Different Kinds Of Onions
The Telegraph tried out the new onion at a local Asda store, and found they didn't cause any discomfort, even after chopping up the entire thing. But if it spreads to the U.S., you're going to have to come up with a better excuse for your tears after watching the finale of Parenthood. (Sniff.)
Photo: Getty Images


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Tottenham and Manchester City will face each other in an all-English quarter-final of the Champions League next month.
Last year's beaten finalists Liverpool received arguably the most favourable draw after being paired with Porto, while Manchester United face a daunting tie against Barcelona.
United and Liverpool will meet in the semi-finals if they reach the last four, with Tottenham or Manchester City facing the winner of the quarter-final between Ajax and Juventus.
The first legs of the quarter-finals will take place on April 9 and 10, with the second legs on April 16 and 17.
Manchester City won both of their Premier League ties with Tottenham last season and also beat Mauricio Pochettino's side at Wembley earlier in this campaign. The two teams meet again in the league just days after the second leg, on April 20.
Manchester United's tie against Barcelona means caretaker manager Ole Gunnar Solskjaer will enjoy another trip to the Nou Camp, where he scored the winner in United's Champions League final win over Bayern Munich in 1999.
United were drawn as the away team for the first leg but the tie had to be reversed, as UEFA had stipulated in advance following advice from local authorities that they and City could not play at home on successive nights.
Former Liverpool goalkeeper Chris Kirkland was delighted by the draw, telling Sky Sports News: "I'd prefer being at home for the second leg but I'm extremely happy.
"Let's not disrespect Porto because they got to this stage for a reason, but they won't be looking forward to that tie."
Former Manchester City boss Stuart Pearce added: "I think Liverpool have gone as favourites now for the competition, being that side of the draw."
"A great occasion, the sort of games that Manchester United are used to and it will be a great night."


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Clean Breathing in Production Homes
For the best ventilation performance, whole-house air distribution is key.
With houses today being built with tighter and tighter envelopes, ventilation systems play a more important role than ever before. Indoor air quality (IAQ),comfort, and both first cost and operating costs have become top priorities for production housing. Through our experience building houses with the Department of Energy's Building America program,and its partner, the Louisiana Pacific Engineered for Life (EFL) program,we believe that the central-fan-integrated supply with fan cycling approach is the best value in basic ventilation strategies for production builders.
We know that, with single-thermostat systems, periodic whole-house mixing is critical to providing the best overall level of perceived IAQ and comfort. Distribution plays a large role in our ventilation strategies, not just for the dilution of pollutants that could harm residents, but for the dilution of pollutants that probably won't harm them—but will annoy them—pollutants such as stuffiness and odors. And just as important, our strategies often allow us to guarantee comfort, defined as a difference of no more than 3°F from the center of any room to the thermostat location. That is hard to do in two-story or large one-story plans without fan cycling. An alternative would be to parallel multiple temperature sensors, but the end result would still be to energize the central system.
Controlled mechanical ventilation has always been a cornerstone of systems-engineered building designs such as ours.Mechanical ventilation should first deal with removing the most offending pollutants where they are generated, and then deal with diluting the remaining pollutants. The removal of pollutants is typically accomplished with small spot exhaust fans in the kitchen, baths, and laundry. The dilution of pollutants is accomplished with supply, exhaust, or balanced wholehouse ventilation fans, and with ducts that distribute less-polluted outdoor air throughout the living space, including closed rooms.
How the System Works
For production home builder designs, the most important aspect of our controlled mechanical ventilation system for pollutant dilution is central-fan-integrated supply ventilation. A nominal 6-inch diameter insulated duct with an outside air intake is connected to the return side of the central air handler unit, and a fan-cycling control unit automatically operates the blower when there is no thermostat demand and the blower has been inactive (see Figures 1,2, and 3).With this system, the distribution of ventilation air is assured, regardless of the normal operation of cooling and heating.
This constitutes the core ventilation system. It can be adapted to various climates and situations, as follows:
1. In severe cold climates (>8,000 heating degree-days), continuous exhaust ventilation can be added to balance the supply ventilation flow.
2. Continuous-exhaust ventilation can be added to increase the supply ventilation flow above that which the supply ventilation system can reasonably provide by itself.
3. Both to close the outside air duct when the fan is not operating,and to limit the amount of ventilation air supplied if the fan has been on longer than needed for ventilation, a motorized damper in the outside air duct, and an AirCycler fan recycling and vent (FRV) control unit can be installed.
4. To reduce energy consumption an electronically commutated motor (ECM) fan can be installed. These fans are set to operate continuously on low speed, except in wet-coil climates,where they are set to operate with an off delay period after a cooling cycle. (An AirCycler fan recycling (FR) control unit is set for 6 minutes fan-off time and unlimited fan-on time.)
At times,we have used exhaustonly ventilation. In this case, the fan cycling control is used as a distribution and mixing tool and is set to operate the central system blower for 10 minutes, if it has been inactive for 50 minutes.We chose this 17% blower duty cycle to distribute ventilation air throughout the conditioned space after extensive tracer gas testing.
However, our production homebuilding clients like the central-fanintegrated supply ventilation system for the following reasons:
1. Ventilation air comes in from one known location, and that location is selected for its air quality. (For example, ventilation air does not come from the garage, the attic, or the subslab.) The outside-air intake is usually on a gable end, or if the roof is full hip,we often drop a small soffit inside the garage just far enough to get to the outside wall. (If the roof is full hip, the insulated and sealed duct goes through the soffit and the wall to a wall cap on the outside, far away from the driveway and its accompanying fumes.)
2. Unlike exhaust ventilation systems, the supply ventilation system provides filtered air. The air is also preconditioned when the heating-and-cooling system is operating.
3. The house is slightly positively pressurized with conditioned air, which acts against any infiltrating air. (The house may be depressurized if the sum of the intermittent exhaust flow is greater than the supply flow.However, since we don't have any natural draft combustion appliances inside conditioned space,and most exhaust flows are only for short bursts,this is not a concern.)
4. When we use the central air handling system to draw in and distribute ventilation air,we are using a system that will be operational,and will be maintained,over the long term;the motor,bearings,and so forth are designed for continuous duty.
5. The periodic air circulation,even with no thermostat demand,improves overall comfort control.
6. The system first cost is low,and the operational cost has been consistently below the low budget guaranteed by the Engineered for Life program.(The operating cost of our system is more than that of a simple exhaust fan,but a fan alone would not provide whole-house distribution and mixing,which we know is needed to avoid stuffiness and temperature variations.)
7.The HVAC contractor is responsible for everything.We don't have to cross trades,with electricians installing fans and ducts,as usually happens with other ventilation systems.
Hesitations Resolved
Our experience creating ventilation systems has given us answers to some frequently asked questions from builders and homeowners.
In hot humid climates,our clients sometimes ask, Won't bringing in hot-humid outside air make the house feel uncomfortable? The answer is,No.We are simply trading controlled ventilation for random and uncontrolled air leakage.
However,to maintain year-round humidity control for clients (some production home-building clients and almost all our custom-home clients) in hot humid climates,we have been installing a standalone dehumidifier that removes moisture even when the thermostat is satisfied.For noncustom homes,the dehumidifier we use is a standard 40- pint-per-day unit that installs under the air handler unit in an interior closet with a louvered door. These dehumidifiers have a built-in dehumidistat and a condensate collection pan that can be plumbed directly to the cooling system condensate line. The dehumidifier,with its dehumidistat,is in the return air path (air from outside the interior closet passes through the louvered door),where it can sense the level of humidity in the recirculating air. The fan cycling control ensures that the dry air is periodically distributed throughout the house,even when there is no thermostat demand.
Fan Noise
Some housing professionals involved with mobile homes have suggested that noisy airhandling systems would be a barrier to the success of central-fan-integrated ventilation in these homes. After well over 1,000 installations in the Building America Program and the EFL program that have gone through at least one heating and cooling season, no contractor or customer has voiced any complaint about system noise. In fact, when inside many Building America houses, with normal background noise, you have to strain your ears, or put your hand to a register, to be sure the system is on.We don't think that air handler noise would be a problem in mobile homes either, as long as extra care is taken in the HVAC system design.
Room Temperature Air Distribution
Some people have suggested that operating the air-handling system during the
heating season,without the heat being on,would be a barrier to the success of central-fan-integrated ventilation.In one Las Vegas subdivision,despite our advice to the engineer about sizing the cooling equipment,the air handling systems in Building America homes were oversized by at least 40%. This caused excessive air flow from the supply registers, which evoked some complaints about cool air in the bedrooms the first winter. The short-term solution was to explain to the occupants how the ventilation system worked,and to adjust supply registers to avoid blowing air directly on sedentary people. The long-term solution was to reduce the size of the equipment.With proper design and installation, the problem evaporated. The central-fan-integrated supply ventilation system is still the ventilation system of choice for the builder and the mechanical contractor, and in that market, the Building America/EFL houses are outselling the competition almost two to one.
First Cost
For our production builder clients, the costs of materials and installation for the basic central-fan-integrated supply ventilation system, with fan cycling control, has ranged from $125 to $200. A rule of thumb for new construction ventilation is that every duct pickup or duct drop costs about $75. Since the fan cycling control costs about the same as one pickup or drop, the entire centralfan- integrated supply system costs about $150. That compares very favorably to a separately ducted, multipoint supply ventilation system that has a total cost of at least $550, with two pickups (outside air inlet and house recirculation inlet), four drops, and a minimum $100 blower.
Operating Cost
Some critics have suggested that operating the relatively large air handler unit blower for ventilation would not be energy efficient. Those suggestions were based on computer simulations that made one or more of the following assumptions:
• The blower would be operated continuously rather than intermittently with the fan cycling control.
• The building envelope would not be the superior envelope designed and used by Building America,which allows for smaller cooling and heating equipment (all of which meet or exceed Energy Star performance);this equipment,when properly sized,does not short-cycle.In the shoulder months,the properly sized system may have short run times to meet the thermostat setpoint,but there will be long periods between cycles with no thermostat demand. Therefore, it will run for short periods infrequently.
• The air distribution system would not be well sealed or not be installed inside conditioned space,or duct performance and duct location would not be considered important enough to account for.
Our own DOE-2 computer simulations for several climates estimated blower operating cost to be $50–$60 per year on average.We then monitored several of our Building America homes for actual system run times to determine the electrical energy consumed to operate the central system blower for ventilation only.Results for three homes in the Chicago area showed that blower run times for ventilation hit a maximum in the swing season months of May and October,when little heating or cooling was occurring,and slid to minimums in the peak winter and summer months,when the blower was operating often for space conditioning,which required little blower operation for ventilation only (see Table 1).For a 350W blower (nominal 2.5 ton cooling system) and at 8¢/kWh,the cost to operate the blower for ventilation during the swing season months was less than $5 per month,and it went down to less than $1 per month in the center of the heating and cooling seasons.Even if it stayed at $5 per month every month,the annual operating cost would still be only $60—hardly excessive.
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