Temporal discrimination and a free-operant psychophysical procedure.

Pigeons were presented a series of keylight time periods (separated by blackouts) during which two response keys were lit, one by blue light and the other either by orange or green. Blue-key responses changed the color on the other key. Orange-key responses sometimes produced food during the first half of a time period; green-key responses sometimes produced food during the second half. In three experiments, the probability of a green-key response increased as a function of elapsed time. Experiment 1 compared performance when the duration of the keylight periods was varied across a wide range. Discrimination of performance was similar across the range of durations. Experiment 2 varied both relative reinforcement rate and the local reinforcement rate for orange-key and green-key responses. These manipulations produced changes in response bias but not discrimination sensitivity. Experiment 3 varied the local temporal placement of reinforcers within time periods and demonstrated that choice behavior was affected by differential reinforcement at different points during the time periods. The results were consistent with previous research on duration discrimination that used psychophysical trials procedures.     

Capturing environmental affordances: Low‐income families identify positive characteristics of a hotel housing solution

This qualitative study describes the positive characteristics of an extended‐stay hotel as identified by low‐income families that resided there. Interviews were conducted with ten hotel residents using a semi‐structured interview guide and participant photographs to elicit a deeper understanding of experiencing home at a hotel. Framed in the theoretical perspective of environmental affordances, findings suggest that despite discomforts of the hotel environment, residents were still able to enjoy family independence, social engagement, a sense of safety and connection to a community context. The findings of this study may help practitioners gain a balanced perspective of non‐ideal housing conditions for planning interventions. Even in these conditions, positive characteristics can be identified to reinforce family functioning and well‐being. Copyright © 2010 John Wiley & Sons, Ltd.     

From wealth to well-being? Money matters,but less than people think

While numerous studies have documented the modest (though reliable) link between household income and well-being, we examined the accuracy of laypeople's intuitions about this relationship by asking people from across the income spectrum to report their own happiness and to predict the happiness of others (Study 1) and themselves (Study 2) at different income levels. Data from two national surveys revealed that while laypeople's predictions were relatively accurate at higher levels of income, they greatly overestimated the impact of income on life satisfaction at lower income levels, expecting low household income to be coupled with very low life satisfaction. Thus, people may work hard to maintain or increase their income in part because they overestimate the hedonic costs of earning low levels of income.     

On Categorical Equivalences of Commutative BCK-algebras

A commutative BCK-algebra with the relative cancellation property is a commutative BCK-algebra (X;*,0) which satisfies the condition: if a ≤ x, a ≤ y and x * a = y * a, then x = y. Such BCK-algebras form a variety, and the category of these BCK-algebras is categorically equivalent to the category of Abelian ℓ-groups whose objects are pairs (G, G ₀), where G is an Abelian ℓ-group, G ₀ is a subset of the positive cone generating G ⁺ such that if u, v ∈ G ₀, then 0 ∨ (u - v) ∈ G ₀, and morphisms are ℓ-group homomorphisms h: (G, G ₀) → (G′,G′₀) with f(G ₀) ⫅ G′₀. Our methods in particular cases give known categorical equivalences of Cornish for conical BCK-algebras and of Mundici for bounded commutative BCK-algebras (= MV-algebras). This revised version was published online in June 2006 with corrections to the Cover Date.     

How pigeons discriminate the relative frequency of events.

This study examined how pigeons discriminate the relative frequencies of events when the events occur serially. In a discrete-trials procedure, 6 pigeons were shown one light nf times and then another nl times. Next, they received food for choosing the light that had occurred the least number of times during the sample. At issue were (a) how the discrimination was related to two variables, the difference between the frequencies of the two lights, D = nf - nl, and the total number of lights in the sample, T = nf + nl; and (b) whether a simple mathematical model of the discrimination process could account for the data. In contrast with models that assume that pigeons count the stimulus lights, engage in mental arithmetic on numerons, or remember the number of stimuli, the present model assumed only that the influence of a sample stimulus on choice increases linearly when the stimulus is presented, but decays exponentially when the stimulus is absent. The results showed that, overall, the pigeons discriminated the relative frequencies well. Their accuracy always increased with the absolute value of the difference D and, for D > 0, it decreased with T. Performance also showed clear recency, primacy, and contextual effects. The model accounted well for the major trends in the data.     

Relative Value Units: Using the New “Currency” for Measuring Clinical Productivity in a Productivity/Incentive Plan

This paper presents an overview of a productivity/incentive plan for faculty in an academic medicine center's department of behavioral medicine and psychiatry. The model utilizes the Resource-Based Relative Value Scale (RBRVS) for its measurement of clinical productivity. The paper provides an introduction to RBRVS terminology and how the RBRVS system was developed. The productivity/incentive plan developed for the Department of Behavioral Medicine and Psychiatry, West Virginia University School of Medicine, Morgantown, is described. The advantages and limitations of utilizing Relative Value Units (RVUs) in a productivity model are discussed. The paper may provide helpful insights to those charged with developing productivity/incentive plans at other academic health science centers.     

Political Power and Race Relations in South Africa: African Attitudes Before and After the Transition

When an oppressed majority finally gains political power, what happens to its attitudes to its erstwhile oppressor, and to its perceptions and feelings about its socioeconomic disadvantages that were established during its oppression? Longitudinal data from pre- and post-transition surveys of black South African college and high school students indicate marked reductions in perceptions of and outrage about intergroup socioeconomic inequity and deprivation relative to English-speaking and Afrikaans-speaking whites, but no change in attitudes toward these groups or toward whites in general. The findings are discussed in terms of contemporary theory and research on justice, intergroup relations, and group conflict. Some tentative implications for the prospects for a democratic political culture in South Africa are noted.     

The Freedom-based Account of Solidarity and Basic Income

Real-libertarianism, as it is expressed in Philippe Van Parijs' recent monograph Real Freedom for All is characteristically committed to both self-ownership and 'solidarity’ with the infirm or handicapped. In this article it is argued that the conception of (real) freedom that is used to endorse self-ownership is inconsistent with the conception of (social) freedom or opportunity that is used to justify transfer payments to those with no or low earning capacity. The problem turns around the question whether one's freedom consists in the access one has to a share of the social product or in the measure of economic self-sufficiency one enjoys. Accordingly the role of private property in external resources as a condition for freedom is unclear: is it the basis of people's capacity for self-determination or is it the basis of people's bargaining power? Van Parijs' commitment to self-ownership suggests the former, his commitment to solidarity suggests the latter. A similar ambivalence is pointed out in his argument for a universal basic income, for which Real Freedom for All is so well-known.     

不确定性风险选择的抱负水平—相对效用整合理论

本文认为不确定性风险决策备择方案的选择标准既不是规范效用理论所主张的效用最大化,也不只是研究者们基于西蒙有限理性决策理论而提出的抱负水平,而是存在于决策不同阶段上的、由启发式策略控制着的这两种标准的整合,我们称之为抱负水平－相对效用整合标准。为此,我们在研究抱负水平结构的基础上提出了负险选择的抱负水平－相对效用整合理论及其支持性研究证据,并就有关问题进行了讨论与思考。指出抱负水平－相对效用整合是风     

Effects of income on drug choice in humans.

The effects of income (money available to spend during the experimental session) on human choice were examined in a concurrent-schedule arrangement. Subjects were 7 nicotine-dependent smokers, and reinforcers were puffs on the subject's usual brand of cigarette ("own") and puffs on a less preferred brand of cigarette with equal nicotine content ("other"). Across sessions, income varied and the price of the two reinforcers was held constant, with the other puffs one fifth the price of the own puffs. As income increased, consumption of own puffs increased while consumption of the less expensive other puffs decreased. These effects of income on choice were highly consistent across subjects. For some subjects, however, income had little effect on total puff consumption. Finally, an additional condition examined whether price and income manipulations would have functionally equivalent effects on choice by repeating an income condition in which the price of the other brand was increased. Although the increased price of the other puffs decreased their consumption in 4 subjects, 2 subjects showed increased consumption of the other puffs at the higher price. The results, when defined in economic terms, indicate that the own puffs were a normal good (consumption and income are directly related), the other puffs were an inferior good (consumption and income are inversely related), and the direct relationship between consumption of the other puffs and their price is defined as a Giffengood effect. The latter result also suggests that for these 2 subjects, price and income manipulations had equivalent effects on choice. These results extend findings from previous studies that have examined the effects of income on choice responding to human subjects and drug reinforcers, and provide a framework for further experimental tests of the effects of income on human choice behavior. Methodological and theoretical implications for the study of choice and for behavioral pharmacology are discussed.