A cost-benefit analysis of demand for food.

Laboratory studies of consumer demand theory require assumptions regarding the definition of price in the absence of a medium of exchange (money). In this study we test the proposition that the fundamental dimension of price is a cost-benefit ratio expressed as the effort expended per unit of food value consumed. Using rats as subjects, we tested the generality of this "unit price" concept by varying four dimensions of price: fixed-ratio schedule, number of food pellets per fixed-ratio completion, probability of reinforcement, and response lever weight or effort. Two levels of the last three factors were combined in a 2 x 2 x 2 design giving eight groups. Each group was studied under a series of six FR schedules. Using the nominal values of all factors to determine unit price, we found that grams of food consumed plotted as a function of unit price followed a single demand curve. Similarly, total work output (responses x effort) conformed to a single function when plotted in terms of unit price. These observations provided a template for interpreting the effects of biological factors, such as brain lesions or drugs, that might alter the cost-benefit ratio.     

Manipulation of self-destruction in three retarded children

The study attempted to isolate some of the environmental conditions that controlled the self-destructive behavior of three severely retarded and psychotic children. In the extinction study subjects were placed in a room where they were allowed to hurt themselves, isolated from interpersonal contact. They eventually ceased to hurt themselves in that situation, the rate of self-destruction falling gradually over successive days. In the punishment study, subjects were administered painful electric shock contingent on the self-destructive behavior. (1) The self-destructive behavior was immediately suppressed. (2) The behavior recurred when shock was removed. (3) The suppression was selective, both across physical locales and interpersonal situations, as a function of the presence of shock. (4) Generalized effects on other, non-shock behaviors, appeared in a clinically desirable direction. Finally, a study was reported where self-destructive behavior increased when certain social attentions were given contingent upon that behavior.     

Derivation of likelihood-ratio tests for Guttman quasi-simplex covariance structures

In this paper, maximum-likelihood estimates have been obtained for covariance matrices which have the Guttman quasi-simplex structure under each of the following null hypotheses: (a) The covariance matrix , can be written asTT + where and are both diagonal matrices with unknown elements andT is a known lower triangular matrix, and (b) the covariance matrix *, is expressible asT*T + I where is an unknown scalar. The linear models from which these covariance structures arise are also stated along with the underlying assumptions. Two likelihood-ratio tests have been constructed, one each for the above null hypotheses, against the alternative hypothesis that the population covariance matrix is simply positive definite and has no particular pattern. A numerical example is provided to illustrate the test procedure. Possible applications of the proposed test are also suggested.Adapted from portions of the author's dissertation under the same title submitted to the Department of Psychology, University of North Carolina, in partial fulfillment of the requirements for the Ph.D. degree. The author wishes to express his gratitude to his thesis chairman Dr. R. Darrell Bock and to his committee members Professors Samarendra Nath Roy, Lyle V. Jones, Thelma G. Thurstone, and Dorothy Adkins. Indebtedness is also acknowledged to Dr. Somesh Das Gupta who was quite helpful during the initial stage of the study.Formerly at the Department of Psychology, Indiana University. The author is grateful both to Indiana University and University of North Carolina for the support extended to him during his doctoral studies.     

A CROSS-CULTURAL STUDY OF SOCIAL DESIRABILITY JUDGMENTS

Etude interculturelle des jugements de “dêsirabilité” sociale. — On compare les estimations faites sur la désirabilité sociale de 143 items de personnalité par 100 étudiants de L'Université de L'Indiana et par 100 étudiants avancés de L'Université de Nagpur. Les deux séries de valeurs corrèllent à .61. Les deux groupes diffèrent significativement dans leurs jugements pour 55 des items. Ces différences peuvent être interprétées selon la manière dont divers aspects du comportement sont considérés par des gens appartenant à des cultures différentes. Les résultats tendent à suggérer que les étudiants indiens mettent fortement L'accent sur le conformisme social, les relations interpersonnelles et une atmosphère saine et paisible, tandis que leurs homologues américains aspirent à obtenir autonomie, pouvoir, succès, bonheur et richesse. Les étudiants américains attribuent également une grande valeur à la plupart des items qui sont en relation avec le désir de réussite. Les résultats sont discutés en référence à des données antérieures.     

Helping Unrelated Strangers: Physical and Psychological Reactions to the Bone Marrow Donation Process Among Anonymous Donors1

The development of models that predict outcomes of voluntary action is important for practitioners who manage large groups of volunteers. In accordance with this goal, a path model was generated linking predonation characteristics of volunteer marrow donors to postdonation physical and psychological reactions. Questionnaire data were collected from 343 individuals registered to donate marrow to unrelated strangers at 3 time points: shortly predonation, shortly postdonation, and 1-year post- donation. Although donors had generally positive reactions to donation, a substantial minority reported ambivalence about donating, physical difficulty with donation, and negative psychological reactions postdonation. In addition, our data suggest that predonation ambivalence is a central predictor of postdonation reactions, even after other donor characteristics are taken into account. These results have practical implications for the recruitment of volunteers, and suggest important variables to be considered in evaluating potential bone marrow donors.     

Response Timing Accuracy as a Function of Movement Velocity and Distance

In two experiments, patterns of response error during a timing accuracy task were investigated. In Experiment 1, these patterns were examined across a full range of movement velocities, which provided a test of the hypothesis that as movement velocity increases, constant error (CE) shifts from a negative to a positive response bias, with the zero CE point occurring at approximately 50% of maximum movement velocity (Hancock & Newell, 1985). Additionally, by examining variable error (VE), timing error variability patterns over a full range of movement velocities were established. Subjects (N = 6) performed a series of forearm flexion movements requiring 19 different movement velocities. Results corroborated previous observations that variability of timing error primarily decreased as movement velocity increased from 6 to 42% of maximum velocity. Additionally, CE data across the velocity spectrum did not support the proposed timing error function. In Experiment 2, the effect(s) of responding at 3 movement distances with 6 movement velocities on response timing error were investigated. VE was significantly lower for the 3 high-velocity movements than for the 3 low-velocity movements. Additionally, when MT was mathematically factored out, VE was less at the long movement distance than at the short distance. As in Experiment 1, CE was unaffected by distance or velocity effects and the predicted CE timing error function was not evident.     

Substitution and caloric regulation in a closed economy.

Three experiments were conducted to study the effect of an imperfect substitute for food on demand for food in a closed economy. In Experiments 1 and 2, rats pressed a lever for their entire daily food ration, and a fixed ratio of presses was required for each food pellet. In both experiments, the fixed ratio was held constant during a daily session but was increased between sessions. The fixed ratio was increased over a series of daily sessions once in the absence of concurrently available sucrose and again when sucrose pellets were freely available. For both series, increases in the fixed ratio reduced food intake, but body weight was reduced only in the no-sucrose condition. In the sucrose condition, body weight and total caloric intake (sucrose plus food) were relatively unaffected by increases in the fixed ratio. At all fixed ratios, food intake was proportionally reduced by the intake of sucrose. In Experiment 3, monkeys obtained food or saccharin by pressing keys; the fixed ratio of presses per food pellet was increased once when tap water was each monkey's only source of fluid, again when each monkey's water was sweetened with saccharin, and a third time when each monkey had concurrent access to the saccharin solution and plain water. Increases in the fixed ratio, but not the intake of the saccharin solution, reduced each monkey's food intake. Because neither rats' sucrose nor monkeys' saccharin intakes affected the slope of the respective demand curves for food, monkeys and rats increased their daily output of presses and thereby defended their daily intake of those complementary elements of food. However, sucrose reduced rats' food intake. The relative constancy of body weight and total caloric intake in the sucrose condition is consistent with the possibility that rats tended to regulate caloric intake.     

The “good manager”: Sex-typed,androgynous, or likable?

Recent studies have indicated that people describe a “good manager” in masculine terms. It was hypothesized that this could simply reflect cultural stereotypes, rather than people's perceptions of what combination of traits is desirable in a leader. In Experiments 1 and 2, subjects were presented managerial profiles ascribing all masculine, all feminine, or a combination of masculine and feminine traits (i.e., “androgynous” profiles) to hypothetical managers. Feminine-trait combinations were rated as significantly less desirable than either masculine or androgynous combinations, which were rated as equally desirable. Thus, while femininity per se was not seen as desirable in a leader, it was not viewed as a liability when combined with masculinity, a corroboration of much behavioral research on androgyny. Experiment 3 varied trait likableness and sex-role orientation. Experiments 1 and 2 were replicated for unlikable traits. Surprisingly, the opposite pattern was obtained for likable traits: the feminine combinations were rated as the most desirable, and the masculine combinations were rated as the least desirable. The results are discussed in the context of early research on impression formation and recent work on social cognition.