An extension of the partial credit model with an application to the measurement of change

The partial credit model is considered under the assumption of a certain linear decomposition of the item × category parameters _ih into basic parameters _j. This model is referred to as the linear partial credit model. A conditional maximum likelihood algorithm for estimation of the j is presented, based on (a) recurrences for the combinatorial functions involved, and (b) using a quasi-Newton approach, the so-called Broyden-Fletcher-Goldfarb-Shanno (BFGS) method; (a) guarantees numerically stable results, (b) avoids the direct computation of the Hesse matrix, yet produces a sequence of certain positive definite matricesB _k ,k=1, 2, ..., converging to the asymptotic variance-covariance matrix of the . The practicality of these numerical methods is demonstrated both by means of simulations and of an empirical application to the measurement of treatment effects in patients with psychosomatic disorders.The authors thank one anonymous reviewer for his constructive comments. Moreover, they thankfully acknowledge financial support by the Österreichische Nationalbank (Austrian National Bank) under Grant No. 3720.     

Formation of transitivity in conditional matching to sample by pigeons

Four homing pigeons were trained over 5 months in a zero-delay, “arbitrary” matching-to-sample procedure with sample and comparison stimuli presented on any of three response keys. Birds were also required to complete a fixed-ratio 10 requirement on both sample and comparison stimuli to terminate their presentation. The procedure resulted in the establishment of relations that were not specifically trained and that can be characterized by the property of transitivity in a stimulus equivalence context. This result was in contrast with the findings obtained from most previous research with nonhuman subjects.     

Human choice in concurrent ratio-interval schedules of reinforcement.

Seven undergraduates participated in a concurrent-choice experiment with monetary reinforcers. Response-independent analogues of variable-interval and variable-ratio schedules were used to assess whether subjects would maximize reinforcement rate. The optimal pattern of behavior, in terms of maximizing reinforcement rate, involved a large bias toward the ratio alternative, with only occasional sampling of the interval schedule. Most experiments with pigeons, however, demonstrate matching of response rates to reinforcement rates, with only slight biases for the ratio schedule. Although subjects in the present experiment allocated more time to the ratio alternative than required by matching, the magnitude of the bias did not approximate that predicted by a maximizing account. After exposure to clock stimuli correlated with the operation of each schedule, 1 subject's behavior did show a substantial level of bias, increasing the total number of reinforcers obtained, and lay at a point between the predictions of matching and maximizing. The other subjects, however, continued to respond less optimally. The present results can be accounted for by a view of matching that incorporates the effects of delayed reinforcement.     

FACTORS INFLUENCING EMPLOYEES' PROPENSITY TO USE AN EMPLOYEE ASSISTANCE PROGRAM

Using data collected from 1,987 employees at several locations of a large firm, this study investigates relationships between these employees' cognitive and attitudinal perceptions of an employee assistance program (EAP) and their propensity to use it. Familiarity with the program, perceived accessibility of it, and perceived managerial support for it are hypothesized to affect both employees' confidence in the program and their propensity to use it, and confidence in the EAP is further hypothesized to affect propensity to use. LISREL analysis supported the overall model, but the direct paths from the cognitive variables to propensity to use were not supported and confidence in the program was therefore indicated to be an essential mediating variable. Propensity to use an EAP is argued to be an important indicator of effective EAP implementation and suggestions are offered to management for promoting employee confidence in an EAP and ultimately their propensity to use it.     

Valid and more valid? Keys to understanding personal appraisal practices at work

Four empirical studies of the roles of self-report questionnaires, tests, and ratings in employment interviews, staff appraisal, and personnel validation surveys are presented in order to examine the number and relationships of psychological constructs derived from data provided by candidates, employees, and their assessors. Test results are related to different kinds of criteria, including job offers following interview, supervisor ratings on the job, and objective indices of work performance. From the practices reported and observed in these various contexts, a theory of personal appraisal mechanisms in occupational settings is derived using data reduction and linear regression methods. Applications of cognitive information processing theory to self-reports and ratings by individuals, and of exchange theory to the social context of panel discussions among assessors, provide a key to understanding why psychometric measures of personal qualities vary in their power to predict work performance in spite of consistent construct validity.     

Vasopressin, glucose homeostasis, and sucrose taste preferences

Previous research indicates that vasopressin-containing (LE) rats are capable of adapting to the stress of food restriction, whereas vasopressin-deficient (DI) rats cannot adapt to this stressor. It has been postulated that abnormalities in glucose metabolism may be one of the factors leading to the demise of food-restricted DI rats. The present study was conducted to determine if taste preferences are altered in DI animals and if the presentation of exogenous glucose, in the form of sucrose solutions, can ameliorate the effects of the stress of food restriction. Four different concentrations of sucrose solutions were presented to LE and DI rats under the food-restricted condition. In both strains, an 8% sucrose solution was preferred over 0%, 16%, and 32% concentrations, with DI rats consuming more of this concentration than LE rats. Thus, when DI rats had the opportunity of maintaining glucose homeostasis by exogenous supplements, they maintained body weight, displayed no stomach pathology, and survived.     

Memory trace development along a coarse-to-fine dimension; a study supporting a progressively finer attributes theory

This study presents two experiments that demonstrate that the memory trace of a tobe-remembered item develops along a dimension (continuum) from coarse/general to fine/specific. Similarly, forgetting is shown to be a reverse movement along this dimension from fine to coarse, as increasingly less fine attributes are lost. The attribute acquisition pattern of this Progressively Finer Attributes Theory is robust and predictable, valid for experimentally unstructured (Experiment 2) as well as experimentally structured (Experiment 1) material.     

Organizational and extraorganizational factors affecting stress,employee well-being,and absenteeism for males and females

The purpose of this research is to examine separately for males and females, the effects of different sources of job and life stress on the emotional and physical well-being of those individuals, and in turn on absenteeism. Results using a sample of 170 males and 204 females indicated that females experienced higher levels of job stress, absenteeism, and poorer emotional well-being. Patterns of relationships for males and females were similar, however, the data suggest that sex moderates the effects of different sources of stress on emotional and physical well-being and absenteeism. The model developed as a part of this research was more complicated for females than for males.     

Rewards and organizational commitment across structural characteristics: A meta-analysis

This article uses meta-analysis to summarize previous empirical studies which examine the relationship between actual income/pay satisfaction and organizational commitment (OC) across different structural settings. Twenty-one studies with correlational data on the relationship between OC and income, and 27 studies dealing with OC and pay satisfaction are examined; these studies include 23 and 31 independent samples, respectively. The findings reveal a moderator effect related to type of occupation in the OC-income relationship, and to sector in the OC-pay satisfaction relationship. The findings also show the moderating effect of measurement of OC on pay satisfaction. Theoretical and methodological considerations pertaining to the OC-rewards relationship are discussed. Directions for future research and practical implications are indicated.The authors would like to thank HelenJane Shawyer and Marion Lupu for their editorial assistance.     

Women and Language in Susan Griffin's Woman and Nature: The Roaring Inside Her

In Woman and Nature: The Roaring Inside Her, Susan Griffin's embedding of language and culture within the natural world implicitly offers a critique of widespread assumptions, shared by many feminists, that language belongs only to the powerful and that it is inherendy violent. Griffin's depiction of the process through which women come to speech is illuminated by V. N. VofosHnov's work on the multiaccentuakty of language and by Trinh Minh'ha's characterizations of oral traditions. Both authors stress the constant re-creation of language by speakers and listeners.