More on the measurement of spontaneous alternation

Still and MacMillan (1977) suggested the negative of the Phi coefficient (- φ) as a measure of free-trial spontaneous alternation. This new index is compared with the Adjusted Alternation Ratio (AAR), previously developed by Manning (1973b). It is concluded that there are many situations in which the AAR is a more useful measure. Other issues in assessing spontaneous alternation noted by Still and MacMillan are discussed.     

APPLICATION OF A SOCIAL SKILLS TRAINING PROGRAM IN THE MODIFICATION OF INTERPERSONAL DEFICITS AMONG RETARDED ADULTS: A CLINICAL REPLICATION

Six mentally retarded adults, equally divided into two treatment groups, were provided with individualized social skills training programs. Treatment, evaluated via a multiple-baseline design strategy, was sequentially and cumulatively applied across target behaviors over a four-week intervention period. Behavioral observation probes and social validation measures served as the primary dependent variables. Results indicated that (a) treatment was effective for virtually all behaviors across all subjects, (b) improvements occurred for both training and generalization scenes, and (c) behavioral performance was maintained one month following the termination of treatment.     

Tactual and visual alphanumeric suffix effects

Two experiments tested the effects of suffixes on the recall of tactual and visual sequences of alphabetic characters presented at 19 letters per min. Scoring techniques allowed for the differentiation of losses of item and order information. In Experiment I performance decrements were found for both modalities, which were mainly caused by item loss at the more recent part of the serial position curve in the suffix conditions. In Experiment II, these effects were replicated and a non-alphabetic suffix led to greater decrements for both modalities than an alphabetical suffix. While a suffix effect based on the loss of item information is consistent with a sensory trace interpretation of the suffix effect, the presence of a visual suffix effect with slow stimulus presentation is not. Additionally, the greater effect of the non-alphanumeric suffix challenges attentional interpretations. Some possible explanations are proposed.     

The availability explanation of excessive plausibility assessments

The assessment of hypotheses in hypothesis generation involves a comparison between those hypotheses that have been generated (specified) and those that are not generated (unspecified). Experiment 1 was an investigation of an “availability explanation” for subjects' overconfidence in the probability of specified hypotheses. The conjecture is that subjects have difficulty retrieving unspecified hypotheses from memory. Therefore, the underpopulated set of unspecified hypotheses is assessed as less probable then it actually is and the specified set is assessed as more probable. Two manipulations to increase the availability of unspecified hypotheses were investigated. One involved explicitly requesting subjects to populate the unspecified set; the other was a computer presentation of candidate unspecified hypotheses. Results of experiment 1 were that assessment overconfidence for both experimental groups was reduced. The results support the conjecture that the availability heuristic is at least partially responsible for subjects' overconfidence. The main result of experiment 2 was that the overconfidence bias persisted with different assessment methods for both subject-generated and experimenter-supplied hypotheses.     

Subjective contours can facilitate performance in a reaction-time task

Subjective contours were compared with objective contours in their ability to facilitate performance in speeded tasks that required judging the position of a dot or the slope of a line segment relative to the contour. Subjective contours were found to reduce both reaction times and error rates for dot localization but not for the more difficult slope discrimination task. These results add to the growing body of evidence suggesting that subjective contours have functional properties similar to those of objective contours.     

A procedural theory of eye movements in doing arithmetic

A procedural theory of eye movement that accounts for main features of the stochastic behavior of eye-fixation durations and direction of movement of saccades in the process of solving arithmetic exercises of addition and subtraction is presented. The best-fitting distribution of fixation durations with a relatively simple theoretical justification consists of a mixture of an exponential distribution and the convolution of two exponential distributions. The eye movements themselves were found to approximate a random walk that fits rather closely in both adult and juvenile subjects the motion postulated by the normative algorithm ordinarily taught in schools. Certain structural features of addition and subtraction exercises, such as the number of columns, the presence or absence of a carry or a borrow, are well known to affect their difficulty. In this study, regressions on such structural variables were found to account for only a relatively small part of the variation in eye-fixation durations.     

A factorial study of a new measure of authoritarianism

In the present study scores on Ray's Directiveness scale were subjected to Varimax rotation. Three factors explaining more than 50% of the variance of authoritarianism were interpreted and labelled Submissiveness, Dominance and Aggressiveness, respectively. Although these are in line with Ray's earlier conception of the nature of authoritarianism and do, to some extent, support other findings, it is suggested that the Directiveness scale be expanded to accommodate more characteristics of authoritarianism such as rigidity, hostility and superstitiousness.     

A rose is a rose is a rose: Minimalism in perception

The article by Wilcox and Edwards (1982) is discussed in terms of the notion of a Physics necessary for an explanatory theory of Perception. Phenomenological explanations, while true, are rejected as lacking explanatory adequacy. Some examples of succesful computational theories, covering the phenomena Gibson considered basic to an Ecological Physics, are given which are based upon a classical optics.     

Similarity ratings and confusability of lipread consonants compared with similarity ratings of auditory and orthographic stimuli.

Similarity ratings of pairs of lipread consonants were obtained using a 5-point scale. Matrices were constructed showing mean similarity ratings and confusions among stimuli. Both the similarity and the confusion data provide normative data useful for researchers in many areas. Lipread data collected here are compared with similarity ratings of orthographically and auditorily presented consonants collected by Manning (1977). These comparisons provide information about how stimulus similarity both within and between presentation formats may affect information processing of the three types of stimuli. These data are of special interest to researchers studying the visual processing of speech and the effect of format of presentation on recall.