Choice for periodic schedules of reinforcement

Pigeons' responses in the presence of two concurrently available (initial-link) stimuli produced one of two different (terminal-link) stimuli according to identical but independent variable-interval schedules. Responding in the mutually exclusive terminal links was reinforced with food according to fixed-ratio schedules for six pigeons and according to fixed-interval schedules for two pigeons. None of the pigeons matched the proportion of (choice) responses in the initial links to the proportion of the rates of reinforcement obtained during the terminal links. Instead, as the values of each of the terminal-link schedules were increased by a constant amount, the choice proportions for the stimulus associated with the smaller of the two values increased, even though the relative rates of reinforcement during the terminal links decreased. These results are incompatible with those from previous studies with aperiodic (variable-interval or variable-ratio) schedules. The present results do suggest, however, that in transforming aperiodic schedules into their periodic equivalents, it may be necessary to consider the size of the smallest interreinforcement interval comprising the terminal-link schedules.     

Toward Effective Evaluation Of the Culturally Deprived

Attention is focused on some of the factors which may result in the invalidation or distortion of both objective and subjective evaluations of students from the lower socioeconomic strata of the population. These factors include: (a) counselor attitude in evaluation; (b) counselee attitude in evaluation; (c) counselor-counselee value systems; (d) test weaknesses such as low reliability and/or validity and inadequate norms; and (e) a lack of understanding by the counselor and/or counselee of the purpose for testing. Evaluation is an integral part of the counseling process; however, the effectiveness of the evaluative process is dependent upon the counselor's knowledge and sense of responsibility as well as the validity and reliability of the tests.     

The detection of malingering in neuropsychological assessment

Although malingering, or the manipulation of data by the patient, is a problem commonly faced by neuropsychologists, there has been little systematic investigation of this problem. This paper reviews the literature on the detection of malingering in assessment instruments commonly used by clinical neuropsychologists. Criticism of previous research is discussed, and suggestions are made both for future research and for clinical practice.     

STATED WILLINGNESS TO PAY FOR PUBLIC GOODS:

Abstract— In the contingent valuation method for the valuation of public goods, survey respondents are asked to indicate the amount they are willing to pay (WTP) for the provision of a good. We contrast economic and psychological analyses of WTP and describe a study in which respondents indicated their WTP to prevent or to remedy threats to public health or to the environment, attributed either to human or to natural causes. WTP was significantly higher when the cause of a harm was human, though the effect was not large. The means of WTP for 16 issues were highly correlated with the means of other measures of attitude, including a simple rating of the importance of the threat. The responses are better described as expressions of attitudes than as indications of economic value, contrary to the assumptions of the contingent valuation method.     

Effects of Race,Racial Identity Development,and Orientation Style on Perceived Consultant Effectiveness

This study explores Black teachers' preferences for and ratings of consultant effectiveness as a function of consultant race, consultant style, and teacher stage of racial identity development. No significant differences were noted in preferences for either a same- or opposite-race consultant. Participants preferred and rated as more effective an instrumentally oriented consultant.     

Parent and Teacher Ratings in the Assessment and Prediction of Antisocial and Delinquent Behaviors

ABSTRACT Subjects consisted of a sample of two cohorts of approximately 100 boys each whose behaviors were rated by their parents and teachers. Criterion variables included antisocial behavior, based on parent, child, teacher, and interviewer reports, and delinquency, based on parent and child reports in addition to cumulative arrest data taken from juvenile court records. The data suggest that mothers are focused on the daily, irritating behaviors of their sons. Teachers, on the other hand, appear to focus on a relatively small number of items (e.g., child physically attacks others, associates with deviant peers), and thereby provide ratings that are better predictors of delinquency and arrest. When the mothers' ratings were constrained to include only items that were salient for teachers, their predictive validity coefficients approached the magnitude of the teacher coefficients.     

Grading the ‘cultural literacy’ project

The essay examines the argument advanced by E.D. Hirsch, Jr., for instituting ‘cultural literacy’ as a fundamental priority of schools. A number of confusions and equivocations in Hirsch's reasoning are identified, and the propensity of his project to indoctrinate is exposed. Among the features of Hirsch's argument shown to be troubling are his shifting construal of ‘language’, his inconsistency about the requirements of cultural literacy, and his uncritical relation to traditional images of the American past and present. The upshot is to raise the question why Hirsch's project has elicited wide support and praise.     

Mathematica: A flexible design environment for neural networks

Several neural networks were developed inMathematica in order to explore the role of “spiky” neurons in neural network memory simulations. UsingMathematica for this task confirmed its value as a powerful tool for neural network development: It exhibited distinct advantages over other environments in programming ease, flexibility of data structures, and the graphical assessment of network performance.