Testing significance of differences between two chi-squares

This paper presents a way to test the difference between twoX ²'s. The test requires evaluating the difference with respect to theT _m (x) Bessel function. Included is a table of the 5 percent and 1 percent points for the Bessel function with degrees of freedom up to 100.This investigation was supported by National Science Foundation Grant Number GE 9846.     

The Vocational Rehabilitation Counselor on Mental Patient Treatment Teams

This study asked the question: What are the role expectancies of treatment personnel in the treatment community and are they consistent across patients' emotional condition? An 83-item inventory was developed and administered under three different sets of instructions, each characterizing a different patient condition. Treatment staff and administrators were asked to rate items on the basis of the level of expectancy they held for their team vocational rehabilitation counselor. The analyses suggest that treatment staff and counselors do not agree on role expectations and that patient condition is a significant mediating variable.     

Reading and typing

As an extension to an earlier study on typing, an experiment was carried out on skilled touch typists in which they were asked to type texts that differed in word structure and word length. It was predicted from certain assumptions about the reading process that there should be significant effects of structure, length and their interaction. These predictions were confirmed.     

Are thresholds reduced by illusions? An attempt at replication

Three experiments are reported, which are attempts to replicate the finding of Ross and Gregory (1964) that difference thresholds for weights can be lowered by means of the size-weight illusion. Three different procedures were used, the first one (experiment I) being designed to show whether or not changes in a subject's judgement criterion could account for apparent changes in sensitivity. The second method (Experiment II) was a replication of Ross and Gregory's first procedure, in which the standard weight was judged before the comparison. In Experiments I and II a larger illusion was induced than in the original studies, but in Experiment III both the weights and container sizes were practically identical to those used by Ross and Gregory. The procedure was also the same as their most successful procedure (number 3) in which standard and comparison were judged simultaneously. The findings were uniformly negative: there was no evidence of criterion shift when the size-weight illusion was induced nor did we find the lowering of threshold previously reported.     

Control of movement patterns in animals

As a more junior Fellow of the same college in Cambridge as Sir Frederic Bartlett, I am especially glad of this opportunity to join with members of the Experimental Psychology Society in honouring him. It would be superfluous for me to speak here of Sir Frederic's academic achievements: so many of our members are engaged in research on problems which sprung from his pioneering work, and his influence on the development of psychology as a science certainly needs no elaboration by me. But I would like to make one personal remark. I suppose all younger men feel that there are just a very few members of the preceding generation who have achieved a stature which will always be beyond the reach of any of their own contemporaries. Sir Frederic has always been one of those for me. I am speaking here not only of his academic achievements, but of his kindness as a man; and I would like to tell him how much I valued his willingness to share some of the benefits of his experience when I was blundering about on the borders of his subject.     

The bioelectrical activity of cerebellar structures in the freely-moving rat

Electrodes were implanted in the brains of 27 freelymoving rats and the bioelectrical activity of cerebellar cortical structures (lobus simplex, tuber verrais, lobus ansiformis, crus II) and the dentate nucleus was measured simultaneously with the activity of the cerebral cortex and dorsal hippocampus and respiratory rate and motor activity. Different behavioral states were produced by habituation procedures and by elaborating conditional avoidance reflexes to light-flash or click series. In addition, startle reflexes to acoustic stimuli were used to evaluate behavioral state. The following conclusions could be drawn: 1) in the awake rat the various cerebellar structures have clearly distinguishable bioelectrical activity patterns; 2) changes in these patterns depend on the actual behavioral state of the animal; 3) this dependence upon behavior is especially clear in crus II, one of the projection zones of the tactile and proprioceptive afferent nerves in the cerebellar cortex. The changes in the electrocerebellogram of the unrestrained rat may be used as an indicator of the behavioral state of the animal.     

Counselor conditions for self-exploration of college students

This study was designed to determine whether the counselor-offered conditions of empathy, respect, and genuineness promoted self-exploration in clients reporting voluntarily to a university counseling center. Twenty-seven male and 27 female undergraduates comprised the sample of clients; nine male doctoral student interns comprised the counselors. Clients were assigned to an educational, vocational, or personal-social problem category. The instruments used were the Truax Depth of Self-Exploration Scale and the Carkhuff scales of counselor conditions. Significant relationships were found between empathy, respect, and genuineness, and self-exploration in each problem category for counseling center clients of both sexes.