Relative costs and statistical power in the extreme groups approach

The relationship between variables in applied and experimental research is often investigated by the use of extreme (i.e., upper and lower) groups. Recent analytical work has provided an extreme groups procedure that is more powerful than the standard correlational approach for all values of the correlation and extreme group size. The present article provides procedures to optimize power by determining the relative number of subjects to use in each of two stages of data collection given a fixed testing budget.The opinions or assertions contained herein are those of the writers and are not to be construed as official or reflecting the views of the Navy Department.Edward F. Alf, Jr. is also affiliated with the Department of Psychology, San Diego State University.     

Do the mentally retarded have poor memory?

The hypothesis that mentally retarded persons have a short-term memory deficit whixh is due to inadequate rehearsal strategies is reexamined. A reevaluation of results of a number of experiments suggests that normal and retarded persons differ on short-term memory tasks, and the superiority of normals is present from the time of initial stimulus exposure. While some evidence for slope differences in retention curves is found in a few tasks, it is not strong support for memory differences. The hypothesis that “memory” differences are due to differential encoding as a result of more adequate rehearsal by the normal subjects is unacceptable. If this were the case, some differences in slope of retention curves could be expected unless rehearsal beyond the encoding stage was totally precluded. The review points to a need for an empirical reevaluation of the issue with a full recognition that deficits in particular processes may characterize some retarded persons and not others.     

Role perceptions: Variations by sex and roles

A Role Perception Scale utilizing a combined projective-objective methodology was developed to assess female and male perceptions of each of three single roles — work, marriage, and parent — and two combined roles — work-marriage and work-parent. Research participants were 134 college students, 88 females and 46 males. Factor analysis of the objective scale, the only part to be scored, resulted in two major orthogonal factors labeled role engagement and competition factors. Sex and role differences for each factor were analyzed using 2×5 split block analysis of variance design with repeated measures. On three out of the five single and combined roles women perceived more engagement than men. In general males perceived roles as more competitive. These sex differences and patterns identified in within-sex analyses across roles are discussed.Parts of this paper were presented at the American Psychological Association Convention, Washington, D.C., September 1976. Research was supported in part by the Dean's Development Fund, New York University, School of Education, Health, Nursing, and Arts Professions. Both authors are senior authors. The order of names is randomly determined. The authors wish to thank Philip Merrifield and Barbara Hummel-Rossi for their statistical assistance in data analysis.     

Attitudes Toward Male Oral Contraceptives: Implications for Models of the Relationship Between Beliefs and Attitudes1

Four factors (effectiveness, health risks, cost, and convenience) were orthogonally manipulated in a 3 × 2 × 2 × 2 factorial design to determine their relative importance in influencing attitudes toward and intentions to use male oral contraceptives. The experimental design also permitted a test of the assumption of additivity underlying expectancy-value models of attitude and the assumption of absence of context effects. Results were consistent with expectancy-value models of the relationship between beliefs and attitudes. In addition, it was found that health risks and effedtiveness, in that order, were the most important factors influencing receptivity to male oral contraceptives, with the effects of cost and convenience being mediated by these two factors. Sex differences in attitudes toward male oral contraceptives were also observed.     

The effect of alcohol on male aggression toward female targets

This study attempted to determine the effects of alcohol, verbal provocation, and target strategy on male aggression toward female targets. Intoxicated and nonintoxicated male research participants competed with a female confederate in a reaction time task designed to measure aggression. Intoxicated participants responded more aggressively than did nonintoxicated participants. Verbal provocation had no effect on participants' aggressive response. Effects of target strategy and trial outcome lent support to a cognitive disorganization interpretation of the effect of alcohol on aggression.     

The perceived social status of husbands and wives in dual-work families as a function of achieved and derived occupational status

The perception of the general social standing of husbands and wives in dual-work families as a function of their respective achieved and derived occupational statuses was examined experimentally. The results indicated that both the wife's and husband's general social status was a function only of the husband's occupational status; the wife's occupational status had no effect on either her general social status or that of her husband. The one exception to this was the case of the high achieved occupational status wife depressing the social status of the low occupational status husband. The results are discussed in terms of their implications for recent critiques of male-determined stratification models.     

Contrast and undermatching as a function of reinforcer duration and quality during multiple schedules

Eight pigeons pecked keys under multiple variable-interval two-minute variable-interval two-minute schedules. In Experiment 1, the reinforcers were 2, 4, or 8 seconds access to a food magazine. In Experiments 2 and 3, the reinforcers were grains that had been determined to be most-, moderately-, or non-preferred. Both positive and negative behavioral contrast occurred when the reinforcers in one component were held constant and the duration or type of reinforcer obtained in the other component varied. Undermatching occurred when the relative rate of responding during a component was plotted as a function of the relative duration of the reinforcers in that component.     

Aversive procedures: The minnesota experience

Aversive and deprivation procedures for controlling and reducing challenging behaviors have received increasing attention. Many states have adopted guidelines on the use of these procedures treating persons with developmental disabilities. The Minnesota state rule promulgated in October, 1987 requires reviews from both local and state-wide review committees on permitted, but controlled procedures. Data generated from state-wide committees revealed that (a) state operated regional treatment centers (RTCs) employed individual habilitative training programs with controlled procedures more frequently than community-based agencies (b) a higher proportion of RTC submissions were for treatment of self-injury than submissions from community services, and (c) RTCs had a higher usage of mechanical restraints than community facilities with both services settings using manual restraints more frequently than all other controlled procedures combined. Reasons for the above differences in the two service settings were discussed.     

The perception of semantic relations in pictures

Three picture processing experiments are reported that present evidence of an “agent advantage effect,” that is, faster processing of the performer of the action depicted the agent of the action than of the element acted upon (the patient). Experiment 1 demonstrated the effect in a paradigm in which reaction time to manually indicate the location of a target (agent or patient) was faster for agent targets. Experiment 2 demonstrated that the critical time required for subjects to encode the agent was shorter than the time required for encoding patients. Experiment 3 again demonstrated the agent advantage effect in a directed attention paradigm. Together, the results of the experiments indicated that subjects were able to encode agent information faster than patient information. The results also indicated that subjects did not adopt a strategy whereby encoding of patient information was necessarily dependent upon encoding agent information.