Testing for a treatment effect in the presence of nonresponders.
Good (1979, Biometrics 35, 483-489) introduced a new randomization test for the two-sample problem where a proportion 1 - p of the treatment group does not respond to the treatment, and suggested that the Wilcoxon test is not effective for this situation. We show to the contrary that the Wilcoxon test is quite useful when p greater than or equal to .6 and point out an error in his definition of a one-tailed randomization test.
The effects of oral cadmium exposure on passive avoidance performance in the adult rat.
Step-down passive avoidance acquisition and 24 h retention performance were examined in adult rats given daily doses of either 0, 1, or 5 mg/kg cadmium (Cd) (as CdCl2) via the diet. Results indicated that subjects exposed to the 5 mg/kg Cd diet were less likely to step off a safe platform onto an electrified grid floor than controls. The 1 mg/kg subjects did not differ from controls on this acquisition task. None of the groups showed differential performances on a retention test administered 24 h after acquisition training. These results are discussed in terms of recent claims that Cd exposure enhances emotional reactivity in animals.
A new class of numerical sequences and its applications to sine and cosine series
First, it is proved that the class of classical quasi-monotone sequences is not comparable to the newly defined class of sequences of ‘rest bounded variation’. Considering this result, we prove three sample theorems for sequences of rest bounded variation, being analogues of the theorems proved earlier for monotone or quasi-monotone sequences. One of them gives a partial answer to a question raised by R. P. Boas Jr.