Modeling strategy shifts in a problem-solving task

A computer simulation model was fitted to human laboratory data for the Missionaries and Cannibals task to explain (1) the effects upon problem performance of giving a hint, and (2) the effects of solving the problem a second time after one successful solution had been achieved. Most of the variance in the relative frequencies of different moves can be explained by positing that the effect of the hint, or of previous experience in solving the problem, is to cause subjects to switch more promptly from a strategy of balancing the numbers of missionaries and cannibals on both sides of the river, to a means-ends strategy.     

REDUCING TIME LIMITS: A MEANS TO INCREASE BEHAVIOR OF RETARDATES1

A common assumption in special education is that temporal limits for a task should be expanded so that ample time is provided for completing the work. This study describes the opposite strategy of restricting temporal limits to augment academic performance. Three educable retarded children received token reinforcement contingent on the number of correct math problems answered during daily sessions. A reversal design was used to assess the effects of an abrupt reduction in time limits (20-5-20 min) and a graduated sequence of reductions (20-15-10-5-20 min). The graduated sequence resulted in rate increases of correct responding ranging from 125% to 266% and these gains endured when temporal limits were again expanded. In contrast, the abrupt shift produced interfering emotional behaviors and rate decreases in academic performance of 25% to 80%. The findings indicate that systematically restricting temporal limits for an academic task can further enhance the performance of slow learners already maintained by a token system.     

Projective and inductive generation of abstract logics

An abstract logic A, C consists of a finitary algebraA and a closure systemC onA. C induces two other closure systems onA, C _P andC _I, by projective and inductive generation respectively. The various relations amongC, C _P andC _I are determined. The special case thatC is the standard equational closure system on monadic terms is studied in detail. The behavior of Boolean logics with respect to projective and inductive generation is determined.Allatum est die 17 Junii 1975     

Sex-related patient and therapist effects on clinical judgment

The purpose of this investigation was to submit the claim of sex-related bias in clinical judgment to more thorough empirical testing than had been the case in previous research. Patient sex and stereotypic sex-role were factorially varied in a clinical protocol that was sent with related materials to 640 sex-stratified, randomly selected Members and Fellows of APA Division 29 (Psychotherapy). Approximately 30% (N=182) of those contacted returned usable data, including information about their own sex-role traditionalism and evaluation of the hypothetical patients' psychological well-being. Results confirmed the effectiveness of the stereotypic sex-role manipulation. However, no consistent effects were found for any of the four variables of interest considered in isolation or in combination, thereby refuting allegations of covert sex-related discrimination perpetrated under the aegis of psychological appraisal. Favorableness of clinical impressions was not mediated by therapists' self-reported attitudes toward the patients. The study's generally unexpected outcome was tentatively attributed to enhanced professional sensitization to the sociocultural barriers to full psychological functioning in women.This report is based on a master's thesis written by the first author under the sponsorship of the second and submitted in partial fulfillment of the requirements for the MA degree at Vanderbilt University, 1974. The research was supported in part by the Vanderbilt University Research Council. The contributions of Stephen Amira and Joseph M. Schwartz are gratefully acknowledged.     

The professionalisation of counselling in education and its legal implications

The questions posed in this paper concern the relationship between the counsellors' claim to be professional and the acceptance of this claim - and its implications - by the courts who act within the terms of existing legal codes. In addition, the paper seeks to clarify the importance of legal recognition in the process of professional legitimation, and examines the position of counsellors in educational institutions (especially secondary schools) in terms of their current legal status and their acceptance as professional counsellors.     

Can imagery be distinguished from other forms of internal representation? Evidence from studies of information retrieval times

This paper provides support for the notion that images, once formed, are a distinct form of internal representation, processed differently than other forms of internal representation. In two experiments, subjects decided as quickly as possible whether or not named animals had given properties. When imagery was not used, people verified properties more quickly in accordance with how strongly associated the property was with the animal in question. When images of the whole animal were consulted, in contrast, subjects were faster in accordance with increasing size of the property, and not with increasing association strength. However, if subjects imaged only the local region where a property ought to be found, and did not consult an image of the whole animal, the size of a property no longer influenced verification time. These results and their implications for the debate over imagery vs. propositional representation were discussed.     

Cross-modality matches suggest anticipated stage fright a multiplicative power function of audience size and status

Subjects adjusted the sound pressure level of a 1,000-Hz tone or the luminance of a 10° target on a translucent screen to match their anticipated subjective tension in performing before audiences represented by 1–16 color slides of old or young males or females. Consistent with a new theory of social impact, “tension” was a multiplicative power function of the number texponent ≅ .6) of people in the audience and their ages, with older t37-year-old) audiences generating 2–3 times the tension of younger Iteen-age) audiences. Male audiences elicited 50%-40% more tension than females.     

Target position and practice in the identification of letters in varying contexts: A word superiority effect

A forced-choice detection paradigm controlling for postperceptual inference was used to investigate letter identification in three-position displays. Letters from a predesignated set of four targets appeared singly, in strings of noise characters, in unpronounceable nonsense strings, and in words. Subjects knew which context would occur, but did not know which of the three display positions would contain the target. Correct detection data were collected at constant exposure duration over five testing sessions. Overall identification accuracy was higher in words than in all other contexts, the first word superiority effect to be found with targets specified in advance since Reicher’s (1969). This effect remained constant over sessions. An interaction between context type and target position showed enhanced accuracy for initial and terminal letters in words, but depressed accuracy at initial and terminal positions in other contexts. This was interpreted to mean that prior knowledge of context is used to alter the dynamics of perceptual analysis.