Simulation analyses of space use: Home range estimates,variability, and sample size

Simulations of space use by animals were run to determine the relationship among home range area estimates, variability, and sample size (number of locations). As sample size increased, home range size increased asymptotically, whereas variability decreased among mean home range area estimates generated by multiple simulations for the same sample size. Our results suggest that field workers should ascertain between 100 and 200 locations in order to estimate reliably home range area. In some cases, this suggested guideline is higher than values found in the few published studies in which the relationship between home range area and number of locations is addressed. Sampling differences for small species occupying relatively small home ranges indicate that fewer locations may be sufficient to allow for a reliable estimate of home range. Intraspecific variability in social status (group member, loner, resident, transient), age, sex, reproductive condition, and food resources also have to be considered, as do season, habitat, and differences in sampling and analytical methods. Comparative data still are needed.     

Critical levels and magnitude of effects

Researchers sometimes report an effect of an experimental manipulation on a dependent variable in terms of the difference between levels of a certain nuisance variable required in the different experimental conditions to reach a given criterion of behavior. This method, however, may yield illusory impressions about magnitude of effects.     

Concurrent validity of the Woodcock-Johnson psycho-educational battery with regular and learning-disabled students

A comparison of the WISC-R and the Woodcock-Johnson Psycho-Educational Educational Battery (W-J) was made for children with regular and learning-disabled (LD) class placement. The W-J and Wechsler Intelligence Scale for Children-Revised (WISC-R) evidence low to moderate correlations and significant mean differences, indicating that the two tests are measuring somewhat different abilities to somewhat differing degrees. W-J—WISC-R correlations for the regular students exceed those of the LD students in the greater majority of the cases. Rank ordering of the WISC-R subtests and the W-J clusters indicate, as might be expected, that the LD students fare the worst in the WISC-R academic subtests (Arithmetic, Information and Vocabulary) and in the W-J academic clusters. More research needs to be conducted with the W-J before it should be adopted for use in the placement of exceptional children.     

An evaluation of the yellow brick road test through a full prediction-performance comparison matrix

The purpose of the present study was to evaluate the predictive validity of the Yellow Brick Road Test (YBRT) relative to performance in reading as measured by the Metropolitan Achievement Test (MAT). A full prediction-performance comparison matrix was employed to compare three different cutoff scores for the YBRT for the identification of “at-risk” children. Four hundred and fourteen kindergarten-aged children were administered the YBRT, 214 of whom were followed to the end of second grade. It was concluded that the YBRT is a moderately valid instrument for predicting the level of reading achievement in a population with a different average performance level from the normative sample. However, the results of this study failed to support the utility of the test author's suggested use of a score of 120 as the cutoff score. Finally, it is recommended that a prediction-performance comparison study be considered standard methodology for the evaluation of the validity and efficiency of screening instruments.     

Midi-level measurement of social anxiety in psychiatric and non-psychiatric samples

This paper reports the development and assessment of midi-level behavioral measures of social anxiety in the context of two experiments, one studying an analog student sample, the other a psychiatric sample. Judgments on nine categories of clinically practical midi-level behaviors (e.g. Facial Expression, Orienting, Sense of Timing), based on a review of the literature on human ethology and on pilot research, were compared to global judgments of social anxiety and social skill and to physiological arousal. Intraclass correlations exceeded 0.80 for judgments of the global and midi-level behavioral ratings on both samples. Results of correlational analyses indicated that while there were several significant predictors of global skill and anxiety among the midis, the magnitude of the relationship between midis and globals was stronger for the patient than the student sample. Further analyses based on S's heart rate (HR) reactivity suggested that while global ratings did not significantly predict H R in a high social anxiety situation, one midi-level behavioral rating (self-manipulations) did. The clinical utility of the newly developed measures is discussed with particular attention to their practicality for behavior therapy.