An experimental and theoretical investigation of the constant-ratio rule and other models of visual letter confusion

The constant-ratio rule (CRR) and four interpretations of R. D. Luce's (In R. D. Luce, R. R. Bush, & E. Galanter (Eds.), Handbook of mathematical psychology (Vol. 1). New York: Wiley, 1963) similarity choice model (SCM) were tested using an alphabetic confusion paradigm. Four stimulus conditions were employed that varied in set size (three, four or five stimulus elements) and set constituency (block letters: A, E, X; F, H, X; A, E, F, H; A, E, F, H, X), and were presented to each subject in independent blocks. The four interpretations of the SCM were generated by constraining one, both, or neither of its similarity and bias parameter sets to be invariant in across-stimulus set model predictions. The strictest interpretation of the SCM (both the similarity and bias parameters constrained), shown to be a special case of the CRR, and the CRR produced nearly equivalent across-set predictions that provided a reasonable first approximation to the data. However, they proved inferior to the least strict SCM (neither the similarity nor bias parameters were constrained; the common interpretation of the SCM in visual confusion). Additionally, the least strict SCM was compared to J. T. Townsend's (Perception and Psychophysics, 1971, 9, 40–50, 449–454) overlap model, the all-or-none model (J. T. Townsend, Journal of Mathematical Psychology, 1978, 18, 25–38), and a modified version of L. H. Nakatani's (Journal of Mathematical Psychology, 1972, 9, 104–127) confusion-choice model. Both the least strict SCM and confusion-choice models produced nearly equivalent within stimulus set predictions that were superior to the overlap and all-or-none within-set predictions. Measurement conditions related to model structure and equivalence relations among the models, many of them new, were examined and compared with the statistical fit results of the investigation.     

The bias of an estimate of coupled slack in stochastic PERT networks

An earlier paper presented a method for using response times to construct a PERT network representing the mental activities in a task. A key role in this method is played by parameters called coupled slacks. The magnitudes of the coupled slacks are used to test the validity of a PERT model and to deduce aspects of the structure of the network. In a stochastic PERT network, the usual estimate of coupled slack based on the mean completion times can be biased. Distribution-free upper and lower bounds are derived for the bias, and it is shown that the bias approaches zero as the probability of relatively long prolongations increases. It is also shown that the expected value of the estimate of coupled slack between two activities is negative only if the two activities are in a Wheatstone bridge. Finally, an estimate of the increase in completion time due to prolonging an activity, given that the prolongation did in fact increase the completion time, is derived.     

Pupil responses to grammatical complexity of sentences

Measurements of pupil size were taken of nine subjects while they listened to sentences of various length, construction, and content, with the instruction to rate them for comprehensibility. Twenty-one sentence types were rated. Each was assigned, via a transformational grammar, a value of grammatical complexity. Mean pupil dilation during listening as an index of psychological complexity was found to correlate more strongly with grammatical complexity than did subject ratings of sentence comprehensibility. These findings suggest that the pupil may have considerable use as an “on-line” monitor of cognitive load imposed by grammatical complexity of sentences.     

On the role of the anterior cingulate cortex in phonation: A case report

A 41-year-old male patient is presented with a lesion in the anterior cingulate cortex, medial orbital cortex, and rostral striatum bilaterally and supplementary motor area on the left side. The patient first exhibited a state of akinetic mutism which lasted about 6 weeks. During this state, no volitional vocal utterances were made; there were, however, occasional groans of pain. During recovery, the mute phase was replaced by a state in which the patient could whisper but not phonate verbal utterances. About 10 weeks after the accident, phonation was restored. The speech was characterized, however, by monotonous intonation and a very low frequency of spontaneous utterances. While the frequency of spontaneous speech improved noticeably during the following months, emotional intonation remained permanently defective. A comparison of the present case with other cases from the literature as well as experimental monkey data suggest that the anterior cingulate cortex is involved in the volitional control of emotional vocal utterances.     

Alternate antagonism with paradoxical translation behavior in two bilingual aphasic patients

Two patients presenting a pattern of recovery yet unreported in the literature were observed, one in Paris, the other in Montreal. Both patients alternately suffered severe word-finding difficulties in one language while remaining relatively fluent in the other. They retained good comprehension in both of their languages at all times. They were able to translate correctly and without hesitation from the language they could speak well at the time into the language unavailable for spontaneous use, but were unable to translate from their temporarily poor language (which they understood well) into the language which they could speak quite well at the time.     

Very long term memory for tacit knowledge

Very long term memory for abstract materials was examined by recalling subjects who had served in a synthetic grammar learning experiment two years earlier. In that study (Reber & Allen, 1978) we differentiated among several cognitive modes of acquisition, their resultant memorial representations, and their associated decision processes. Two years later and without any opportunity for rehearsal or relearning, subjects still retain knowledge of these grammars to a remarkable degree. Although some differences have become blurred with the passage of time, the form and structure of that knowledge and the manner in which it is put to use remain strikingly similar to the original. That is, differences traceable to acquisition mode and conditions of initial training can still be observed. As in the original study, these results are discussed within the general context of a functionalist approach to complex cognitive processes.     

Factor structure of the WISC-R with Anglos and Mexican-Americans

The present study compared the underlying factor structure of the Wechsler Intelligence Scale for Children-Revised for Anglo and Mexican-American children. Subtests of the WISC-R were administered to 109 Anglo and 123 Mexican-American children ranging from 8 to 15 years of age and were analyzed separately for each group. Three factors emerged for each ethnic classification which corresponded closely to those usually reported for the WISC-R. Coefficients of congruence (.84–.89) between factors given the same name for each ethnic group indicated a high degree of similarity in constructs being measured.     

A comparison of preservice and experienced teachers' perceptions of the school psychologist

The present study compared experienced and preservice elementary school teachers' perceptions of the school psychologist. Thirty-two experienced teachers were matched with a like number of second semester juniors in training. A questionnaire asked each respondent to (a) rank a number of school personnel on their importance, (b) assign a number of referral problems to professionals best equipped to handle them, and (c) to rate the school psychologist's functioning on 11 dimensions. The analysis showed that experienced and preservice teachers agreed about the importance of the school psychologist and the appropriateness of referral problems. Analysis of ratings revealed that experienced teachers had a more negative opinion of the school psychologist's functioning when compared to their novice counterparts.     

Performance as a function of resultant achievement motivation (perceived ability) and perceived difficulty

Subjects worked on a task which was described as either easy or difficult. When the task was thought to be difficult, Ss high in resultant achievement motivation performed better than those low in resultant achievement motivation. However, when the task was perceived as easy, the high motive group performed worse than the low group. These results confirm a prediction from Kukla's attributional theory of performance, in which resultant achievement motivation is conceived as a measure of perceived ability. They are not, however, deriveable from Spence's theory of the effects on performance of objective task difficulty, nor from Weiner's hypothesis concerning the motivational effects of success and failure. On the other hand, Kukla's theory provides an explanation for both the data usually cited in support of Spence's position and those taken to confirm Weiner's hypothesis. The relationship between the present results and Atkinson's theory of achievement motivation, which also hypothesizes an effect of perceived difficulty on performance, is discussed.     

I wish it were true: Confessions of a secret deductivist

The criticisms by S. V. Paunonen and D. N. Jackson (1985, Journal of Research in Personality, 19, 331–342) are examined in detail. Despite the best of intentions, the author remains unconvinced.