Relationships between redundancy analysis,canonical correlation,and multivariate regression

This paper attempts to clarify the nature of redundancy analysis and its relationships to canonical correlation and multivariate multiple linear regression. Stewart and Love introduced redundancy analysis to provide non-symmetric measures of the dependence of one set of variables on the other, as channeled through the canonical variates. Van den Wollenberg derived sets of variates which directly maximize the between set redundancy. Multivariate multiple linear regression on component scores (such as principal components) is considered. The problem is extended to include an orthogonal rotation of the components. The solution is shown to be identical to van den Wollenberg's maximum redundancy solution.This research was supported in part by U.S. Environmental Protection Agency contract 68-02-3402. The author gratefully acknowledges the stimulation of Maurice Tatsuoka and Beth Dawson-Saunders in first interesting him in redundancy analysis, as well as a useful change suggested by Warren Sarle.     

Reliability of headache diagnosis

The literature on diagnosis of head pain associated with psychological factors indicates that these diagnoses rely almost exclusively on self-report criteria. The reliability of self-report criteria for diagnosis of headache has not been previously reported. The present study investigated the reliability of headache diagnosis based on the criteria suggested by the Ad Hoc Committee on Classification of Headache. The results indicated modest rater agreement. It was concluded that the headache literature may be confounded by unreliable diagnostic procedures. Improved methods of classifying headache types using self-report, behavioral, and physiological measures during pain-free and headache states are required before adequate reliability of headache classification can be achieved. It is suggested that reliable and valid measurement and classification would eliminate much of the confusion currently existing in the headache literature.     

The strain of guardianship for men in the United States

This study examined the extent to which control, commitment, and support influenced the strain experienced among men in the U.S. who were acting as guardians for aged adults, an atypical role for such men. A total of 146 male guardians responded to a questionnaire. Results of the study showed that control and commitment were associated with less strain, whereas the use of formal support systems was related to greater levels of strain. Additionally, strain was found to be less prevalent among older guardians.     

A System for Relational Reasoning in Human Prefrontal Cortex

The integration of multiple relations between mental representations is critical for higher level cognition. For both deductive- and inductive-reasoning tasks, patients with prefrontal damage exhibited a selective and catastrophic deficit in the integration of relations, whereas patients with anterior temporal lobe damage, matched for overall IQ but with intact prefrontal cortex, exhibited normal relational integration. In contrast, prefrontal patients performed more accurately than temporal patients on tests of both episodic memory and semantic knowledge. These double dissociations suggest that integration of relations is a specific source of cognitive complexity for which intact prefrontal cortex is essential. The integration of relations may be the fundamental common factor linking the diverse abilities that depend on prefrontal function, such as planning, problem solving, and fluid intelligence.     

The time course of phonological, semantic, and orthographic coding in reading: Evidence from the fast-priming technique

The present experiment employed the fast-priming paradigm in reading (Sereno & Rayner, 1992), in which sentences are silently read while eye-movement-contingent changes are made on a specified target region. In this paradigm, when readers fixate on a specified target word region, a prime word is encountered for a brief duration at the beginning of the fixation and then it is replaced by a target word. Three types of primes were employed:homophones, semantically related, andorthographically similar, and five prime durations were employed: 29, 32, 35, 38, and 41 msec. The primary finding was that significant homophone priming was obtained at prime durations ranging from 29 to 35 msec, whereas significant semantic priming occurred only at the 32-msec prime duration. In contrast, significant orthographic priming occurred at all prime durations. These findings indicate that phonological codes are activated during an eye fixation at least as rapidly as semantic codes. An explanation for the pattern of events is suggested using the framework of an activation-verification model.     

SOCIAL INTERACTIONS IN THREE SUPPORTED EMPLOYMENT OPTIONS: A COMPARATIVE ANALYSIS

Controversy exists over the benefits that workers with severe disabilities accrue under different supported employment options. This study focused upon one benefit of supported employment: social integration. Direct observation procedures were used to assess the social interactions of 37 adults with severe disabilities in 18 employment programs representing three different supported employment contexts (individual, enclave, and work crew). Results indicated that workers employed in individual and enclave programs had significantly more contact with nondisabled persons than did members of work crews. No differences were detected in the social contact rate between disabled and nondisabled workers in individual versus enclave sites. Furthermore, few differences in type of interactions across the three different work options were revealed. Results suggest that both individual and enclave models are capable of facilitating social integration. However, characteristics of specific job sites, more so than the employment model per se, may determine whether a particular employment setting is conducive to social integration.     

On shortening the Expanded Attributional Style Questionnaire

Whitley (in press) described a short form of the Expanded Attributional Style Questionnaire (EASQ). The EASQ was created to remedy the unsatisfactory psychometric properties of the Attributional Style Questionnaire; therefore, the benefits of a short form must be balanced with the possible costs, lower reliability and, hence, lower validity. Data from eight different samples using the EASQ (N = 963) suggest that the best items on the EASQ differ from sample to sample and from dimension to dimension. Further, reliabilities are reduced according to the predictions of the Spearman-Brown formula. Implications of these findings for attributional style research are discussed.