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 difference in mean costs as a pharmacoeconomic outcome variable: power considerations.
The difference in mean costs between a placebo and a drug treated group is used for the pharmacoeconomic evaluation of a new drug. The distribution of costs without treatment (null hypothesis) is determined through hospital records. The sampling properties are established by simulation. The results of the simulation allow determination of a break point of differences corresponding to a given level of significance. For power determination, using this break point, clinical hypotheses are used to generate the distribution of costs under treatment (alternative hypothesis).
Rapid Spatially Coupled AVO Inversion
The Bayesian methodology yields a natural framework for many geophysical inverse problem, see e.g. (Tarantola and Valette, 1982; Tarantola, 1987; Duijndam, 1988a; Duijndam, 1988b). The solution of a Bayesian inverse problem is represented by the posterior distribution. From the posterior distribution the best estimate and the corresponding uncertainty can be extracted and a set of plausible solutions can be drawn.