A method of computing percentile ranks from the logistic distribution function is described. The method was applied to three distributions of number-right scores from the Law School Admission Test, and compared to percentile ranks computed using linear interpolation. (Author/JKS)

Compared 71 patients diagnosed as within schizophrenia spectrum according to second edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-II) with 66 patients having similar diagnoses according to the third edition (DSM-III). Results suggest that findings obtained with DSM-II schizophrenics concerning premorbid competence and…

A true-false measure concerning the interpretation of intelligence quotients (IQ) is presented. The correct responses to the 10 items, and a brief explanation of each, are also included. The author attempts to reveal many misconceptions about the interpretation of IQ scores. (DWH)

Implicit in the work of S. Huck and H. Sandler (1979) is the idea that the concept "rival hypotheses" refers to some kind of alternative explanation. Rather than being threats to internal validity, rival hypotheses, in their view, are interpretations that differ from those of the researcher. This paper broadens the idea to include any…

The relationship between generalizability and validity is explained, making four important points. The first is that generalizability coefficients provide upper bounds on validity. The second point is that generalization is one step in most interpretive arguments, and therefore, generalizability is a necessary condition for the validity of these…

As the 1994 publication manual of the American Psychological Association emphasized, "p" values are affected by sample size. As a result, it can be helpful to interpret the results of statistical significant tests in a sample size context by conducting so-called "what if" analyses. However, these methods can be inaccurate…

A questionnaire study revealed more diversity in testing practices that is commonly realized. (Editor)

Details are presented of a case of acoustic neuroma in which there was a discrepancy between Bekesy sweep-frequency results and those of fixed frequency traces and a tone-decay test. (Author)

Data indicate that the Visual-Sequential Memory subtest of the ITPA and the Knox Cube Test measure different aspects of visual-sequential memory ability. (KW)