A measurement model of women's behavioral risk taking.

The current study was designed to gain a better understanding of the nature of the relationship between substance use and sexual risk taking within a community sample of women (N = 1,004). Using confirmatory factor analysis, the authors examined the factor structure of sexual risk behaviors and substance use to determine whether they are best conceptualized as domains underlying a single, higher order, risk-taking propensity. A 2 higher order factor model (sexual risk behavior and substance use) provided the best fit to the data, suggesting that these 2 general risk domains are correlated but independent factors. Sensation seeking had large general direct effects on the 2 risk domains and large indirect effects on the 4 first-order factors and the individual indicators. Negative affect had smaller, yet still significant, effects. Impulsivity and anxiety were unrelated to sexual health risk domains.     

The semiautomatic Wisconsin general test apparatus

A semiautomatic version of the Wisconsin General Test Apparatus is described along with circuitry. Comparison data are provided for the semiautomatic and manual WGTA obtained under comparable procedures and conditions. Response latencies are given for go/no-go object discrimination problems and subsequent retention tests.     

Test of structural relationships within a proposed exercise and self-esteem model

This study tested structural relationships within a model proposed to explain the manner in which self-esteem changes are associated with exercise experiences. As initially assessed by self-efficacies (EFFs) specific to physical tasks within a training program, we postulated that competence can generalize to feelings of global self-esteem (SE) through an intervening construct of perceived physical competence (PC). Three measures of EFF and two each of PC and SE were administered to 145 people in their mid- to late adulthood. Confirmatory factor analysis examined orthogonal and oblique versions of three measurement models and identified three distinct but correlated factors, each assessed by its hypothesized indicators. Alternative structural equation models were specified and tested using both normal and nonnormal estimation procedures. The proposed model provided the most parsimonious fit and explained 29% of the variance in SE. Confirmation of its structural relationships provides preliminary validity for model use in examining the manner in which exercise experiences influence levels of self-perception.     

Effects of manipulating incentive visibility during the baiting phase of delayed-response problems

Rhesus monkeys were given 960 delayed response (DR) problems. The incentive was either visible or not visible during the baiting phase of each problem, and a 0-, 5-, 10-, or 20-sec intraproblem delay was imposed. Performance was substantially better when the incentive could be seen during the baiting phase. When the incentive was visible during baiting, at all stages of training performance decreased as a function of increased chance levels after short delays, and the rate of improvement with training was comparable after each of the four intraproblem delays. When the incentive was not visible during the baiting phase, an inverse relationship between performance and delay duration became evident only during the later stages of training. On the initial problems performance was at chance levels, and although improvement with training was evident, the rate of this improvement was inversely related to delay duration. The findings were interpreted in terms of Fletcher's orienting response analysis of DR performance.