The operant conditioning of response variability: Free-operant versus discrete-response procedures

The operant conditioning of response variability under free-operant and discrete-response procedures was investigated. Two pigeons received food only if their pattern of four pecks on two response keys differed from the patterns emitted on the two immediately preceding trials. Under the free-operant procedure, the keys remained illuminated and operative throughout each trial. There was little variability in the response patterns that resulted, and the pigeons received fewer than one third of the available reinforcers. Under the discrete-response procedure, a brief timeout period followed each response. Variability increased under this procedure, and the pigeons obtained three fourths of the available reinforcers. Previous successes and failures to produce response variability may have been due to the use or failure to use, respectively, a discrete-response procedure. Respondent effects inherent in the free-operant procedure may encourage the development of response stereotypy and, in turn, prevent the development of response variability.     

A formulation of Erikson's theory of ego identity formation

This paper provides a comprehensive formulation of Erik Erikson's theory of ego identity formation as it pertains to both the identity stage and to the remainder of the life cycle. The structure of the identity stage is discussed in terms of its more universal features and in terms of features more specific to North American society. The role played by “institutionalized moratoria” in influencing the outcome of the identity crisis and subsequent development is discussed in the context of two Eriksonian notions ignored in the literature: the value orientation stages and the struggle between the ego and superego for dominance of the personality. As part of the discussion, several constructive criticisms of Erikson's work are offered with the intent of making the theoretical formulation presented in this paper an appropriate basis for subsequent empirical investigations of his theory. One of the important implications of this paper is that it suggests that questions should be raised regarding the validity of the dominant research strategy currently in use.     

A hardware and software interface for sensing changes in rotary position with an Apple II microcomputer

A design for an Apple II interface that senses relative rotary position and/or motion via a digital potentiometer is presented. A thorough discussion of the circuit’s theory of operation and a fully commented BASIC software listing are included. Suggested applications include an infinite-turn rotary device for psychophysical methods of adjustment, the sensing of rotary translations of a steering wheel in a driving simulator, and a digital tachometer/odometer for tracking performance on stationary exercise bicycles and treadmills.     

Perceived Control in Prison: Its Relation to Reported Crowding,Stress, and Symptoms1

Two studies were conducted to investigate the effects of perceived control in two men's prisons, one housing 181 inmates and the other housing 623 inmates. In both prisons, inmates' perceived control over the environment was found to be significantly related to their ratings of their living accommodations, experienced stress, and physical symptoms, even when type of cell was held constant.     

FUNCTIONAL ANALYSIS AND TREATMENT OF SEVERE PICA

A two-phase functional analysis of a profoundly retarded 19-year-old male's pica facilitated the design of an effective intervention containing no aversive components. In the first analysis, frequent staff-client interaction resulted in 25% and 66% less pica than limited and no interaction, respectively. Paradoxical effects were obtained in the second analysis, where no protective helmet resulted in 38% and 26% less pica than the helmet with face shield and helmet without face shield, respectively. On the basis of these analyses, limited interaction and no helmet conditions were combined in an effective, staff-implemented treatment at a medium-sized institution.     

Test theory and psychometrika: The past twenty-five years

On the occasion ofPsychometrika's fiftieth anniversary, the past twenty-five years' developments in mental test theory are reviewed, with special emphasis on the topics receiving attention in the pages of this journal. (Analogous reviews forPsychometrika's first quarter century were given by Gulliksen and Guilford in 1961.) Much of the recent progress in test theory (and in other branches of psychometrics as well) has been made by treating the problems in this field as being essentially ones of statistical inference. It is concluded that (a) research in test theory is in a healthy state and (b)Psychometrika is an important source of information about that research.     

Interparent agreement on the Personality Inventory for Children: Are substantial correlations sufficient?

Mothers' and fathers' responses on the Personality Inventory for Children (PIC) were compared for 360 clinic-referred children and adolescents. Interparent agreement was measured by several different indices. Correlations between parental pairs of scale T-scores derived from each parent averaged .66 for 13 of the profile scales; 9 of the scales exceeded this value. In contrast, mothers and fathers agreed in the classification of the presence of clinical significance an average of 77% of the time across these 13 scales, and pairs of parental PIC profiles contained an average of 3 scales in disagreement. The type of index used to measure interparent agreement was found to affect the results. The discussion examines the nature of interparent disagreement and addresses the implications regarding the use of fathers as informants on this instrument.This article is based on Thomas A. Hulbert's master's thesis. The authors extend their appreciation to James Orisell and Dena Mussaff for their assistance in data preparation and analysis.