Tests for equality of several alpha coefficients when their sample estimates are dependent

In a variety of measurement situations, the researcher may wish to compare the reliabilities of several instruments administered to the same sample of subjects. This paper presents eleven statistical procedures which test the equality ofm coefficient alphas when the sample alpha coefficients are dependent. Several of the procedures are derived in detail, and numerical examples are given for two. Since all of the procedures depend on approximate asymptotic results, Monte Carlo methods are used to assess the accuracy of the procedures for sample sizes of 50, 100, and 200. Both control of Type I error and power are evaluated by computer simulation. Two of the procedures are unable to control Type I errors satisfactorily. The remaining nine procedures perform properly, but three are somewhat superior in power and Type I error control.A more detailed version of this paper is also available.     

Mathematical formulation of multivariate euclidean models for discrimination methods

Multivariate models for the triangular and duo-trio methods are described in this paper. In both cases, the mathematical formulation of Euclidean models for these methods is derived and evaluated for the bivariate case using numerical quadrature. Theoretical results are compared with those obtained using Monte Carlo simulation which is validated by comparison with previously published theoretical results for univariate models of these methods. This work is discussed in light of its importance to the development of a new theory for multidimensional scaling in which the traditional assumption can be eliminated that proximity measures and perceptual distances are monotonically related.     

REDUCING NONCOMPLIANCE TO FOLLOW-UP APPOINTMENT KEEPING AT A FAMILY PRACTICE CENTER

In this study, we evaluated follow-up appointment keeping at a family practice center. To determine if noncompliance could be reduced, four treatments were implemented: no-treatment control, modified appointment card, free follow-up, and a reduced rate follow-up. Thereafter, the reduced rate follow-up was implemented again to determine the extent noncompliance could be reduced for all eligible patients. Incentives significantly increased follow-up appointment keeping, whereas the modified appointment card was ineffective. A cost analysis suggested that the no-treatment control and modified appointment card conditions were the least expensive, but also the least effective. The incentive conditions were more expensive, but the reduced rate condition generated the most net revenue. Questionnaire data suggested that the incentive conditions had an effect on noncompliance and may be considered for use in other medical settings.     

An alternative test for multisample sphericity

A test for multisample sphericity based on the efficient scores criterion is obtained as an alternative to the likelihood ratio test developed by Mendoza.     

Univariate repeated measures techniques applied to multivariate data

Repeated measures designs in psychology have traditionally been analyzed by the univariate mixed model approach, in which the repeated measures effect is tested against an error term based on the subject by treatment interaction. This paper considers the extension of this analysis to designs in which the individual repeated measures are multivariate. Sufficient conditions for a valid multivariate mixed model analysis are given, and a test is described to determine whether or not given data satisfy these conditions.     

Measures of interobserver agreement: Calculation formulas and distribution effects

Seventeen measures of association for observer reliability (interobserver agreement) are reviewed and computational formulas are given in a common notational system. An empirical comparison of 10 of these measures is made over a range of potential reliability check results. The effects on percentage and correlational measures of occurrence frequency, error frequency, and error distribution are examined. The question of which is the best measure of interobserver agreement is discussed in terms of critical issues to be considered     

LONG-TERM EFFECTS OF OPPOSITIONAL CHILD TREATMENT WITH MOTHERS AS THERAPISTS AND THERAPIST TRAINERS

The follow-up data reported represent a long-term (3 to 9 years out of treatment) evaluation of 40 children who were clients of the Regional Intervention Program (RIP) from 1969 to 1978. As 3-, 4-, and 5-year olds, these youngsters exhibited severe and prolonged tantrums, continual opposition to adults' requests and commands, and physical aggression toward parents. Each child and mother participated in a standardized intervention package modeled after Wahler's Opposition Child Treatment. Results from school and home-based follow-up showed that: (a) commands, demands, or requests made by parents were likely to be followed by former clients' compliance; (b) former clients' social interactions in the home were overwhelmingly positive and their nonsocial behavior was by and large appropriate; (c) parent behavior in the home was consistent with the child management skills taught many years ago; (d) there were no differences between the compliant, on-task, social interaction and appropriate/inappropriate nonsocial behaviors of former clients and randomly selected class peers; (e) there were no differences in teachers' commands, negative feedback, positive social reinforcement, and repeated commands that were directed toward either former clients or randomly selected class peers; (f) both teachers' and parents' rating of former clients on the modified Walker Problem Behavior Checklist were highly correlated; (g) there were no differences in teachers' rating of former clients and class peers; and (h) of all the studied demographic variables, only age that treatment began and family intactness were related to current levels of behavior.     

A significance test for multisample sphericity

The paper obtains a maximum likelihood criterion test for multisample sphericity. The test contains Mauchly's sphericity test as a special case.I would like to thank Professor R. E. Bargmann for his most valuable help.     

视觉追踪作业心理负荷的多变量评估研究

敏感性是心理负荷测量技术可靠性的基本要求。该研究利用主任务绩效、次任务绩效、主观“加权负荷”评定和心率变异变化率四项指标,在计算机模拟情境下对视觉追踪作业心理负荷进行多变量评估实验。结果发现,以上述四项指标为基础建立的“综合加权评估指数”是一项较有效的评估指标,其敏感性远高于任何单独的评定。