Constrained canonical correlation

This paper explores some of the problems associated with traditional canonical correlation. A response surface methodology is developed to examine the stability of the derived linear functions, where one wishes to investigate how much the coefficients can change and still be in an -neighborhood of the globally optimum canonical correlation value. In addition, a discrete (or constrained) canonical correlation method is formulated where the derived coefficients of these linear functions are constrained to be in some small set, e.g., {1, 0, –1}, to aid in the interpretation of the results. An example concerning the psychographic responses of Wharton MBA students of the University of Pennsylvania regarding driving preferences and life-style considerations is provided.Wayne S. DeSarbo, Robert Jausman, Shen Lin, and Wesley Thompson are all Members of Technical Staff at Bell Laboratories. We wish to express our gratitude to the editor and reviewers of this paper for their insightful remarks.     

Impulsivity, caffeine, and proofreading: a test of the Easterbrook hypothesis

Easterbrook's (1959) suggestion that arousal is inversely related to the range of cue utilization has been frequently cited as an explanation for the curvilinear relationship between arousal and performance. There is very little empirical support for this position, however. As a test of the Easterbrook hypothesis, 60 undergraduates who varied in their impulsivity level were given caffeine or placebo and then asked to proofread several passages. Estimates of sensitivity were calculated using signal detection techniques. It was predicted that high arousal would reduce sensitivity to interword errors, which require a broad range of cue utilization, but that the observed levels of arousal would not affect sensitivity to intraword errors, which require a minimal range of cue utilization. A significant crossover interaction between impulsivity and drug for interword errors indicated that caffeine increased the error detection rate of the (less aroused) more impulsive subjects but lowered the error detection rate of the (more aroused) less impulsive subjects. The results of this study support the suggestion that arousal has direct effects on the capacity for simultaneous information processing, independent of its effects on performance speed.     

MANAGEMENT OF INAPPROPRIATE BEHAVIORS OF TRAINABLE MENTALLY IMPAIRED STUDENTS USING ANTECEDENT EXERCISE

The effects of several levels of exercise on inappropriate behaviors of four trainable mentally impaired students were observed. Treatment conditions, which occurred as the first daily activity, included: Phase I, daily alternating conditions of warm-up exercises and jogging at a moderate rate for a short distance; Phase II, daily alternating conditions of no-exercise periods and jogging at a vigorous rate for a moderate distance; and Phase III, jogging at a vigorous rate for a moderate distance on consecutive days. For one student two additional conditions occurred, Phase IV, long-distance jogging on consecutive days at a vigorous rate and Phase V, consecutive days of no exercise. Observations of three inappropriate behaviors of each student occurred immediately after, 1 hour after, and 2 hours after each exercise period. Results indicate a decrease in all three inappropriate behaviors for three of four students and an inverse relationship between the level of exercise and the amount of inappropriate behavior for three of four students. Improvements over existing studies are discussed with suggestions for future research.     

A conditioned weight illusion: Reafference learning without a correlation store

Each of 20 female college students repeatedly judged the weight of a heavy metal cylinder dropped repeatedly (180 times) into her waiting hand. The cylinder came to appear lighter to her when the release of the cylinder was accompanied by the onset of an indicator lamp than when it was not, but only providing the onset of the lamp preceded the release of the cylinder by a half second rather than being simultaneous with it. This conditional illusion has implications for von Holst and Mittelstaedt’s well-known thesis that every neural efference leaves an efference copy or corollary discharge of itself in the nervous system to be compared with concurrent neural reafference. Apparently some types of conditioned-efference leave no copies, and objects lifted in part by such unregistered efforts appear lightened accordingly. The illusion illustrates a form of reafference learning that need involve no correlation store (Held, 1961).     

The pastor as genetic counselor

The pastor as pastoral counselor in the setting of the church can play an important role on a genetic team. This article explores the role the pastor plays in the definitive stage: delivery of information, educating, supporting, and counseling in human genetics. Problems that are encountered by team members, patients, and families, and dominant feelings that seem to exist in couples or individuals who discover that their children have a birth defect or that they themselve are carriers of a faulty gene are revealed and illustrated through clinical examples and interviews. Further suggestions are given on how a constructive team approach can help provide information regarding birth defects and how pastors can help and participate in this process.The Rev.M. Wayne Clark, D. Min., is a United Methodist pastor in Sidney, Iowa, and has completed Care and Counseling's two-year graduate training program for pastoral counselors in St. Louis, Missouri. He has served as a consultant to the Division of Medical Genetics at the University Hospital in Iowa City, Iowa, and has worked with the staff of Regional Genetic Consultation Services of the Iowa State Department of Health. He is a member of A.A.P.C. and a clinical member of AAMFT.     

Effects of prior knowledge on memory for new information

Three experiments examined the effects of prior knowledge on the learning and retention of new information. Subjects learned varying amounts of prior knowledge about individuals referred to by first name/last name combinations. In the first two experiments, subjects more rapidly learned new information about individuals for whom they were given prior knowledge, retrieved this information more slowly, and showed smaller interference (fan) effects. This complex of results is predicted by a spreading activation model in which we assume subjects try to integrate the prior knowledge with the new information in a network fashion. The third experiment, in addition to including conditions of prior vs. no prior experimental knowledge, included well-known names like Ted Kennedy, about which subjects have a great deal of preexperimental prior knowledge. The relationships between conditions of experimental prior knowledge and no prior knowledge obtained in Experiments 1 and 2 were replicated, but the well-known names did not behave simply like the extreme of experimental prior knowledge. In particular, subjects showed the fastest verification of new facts learned about the well-known names, rather than the slowest, as predicted from the spreading activation network model.     

Process, not representation: reply to Radvansky (1999).

The size of fan effects is determined by processes at retrieval, not by whether or not information is represented as situations. Evidence contradicts G. A. Radvansky's (1999) claim that time to retrieve information from a situation does not depend on the number of elements in the situation. Moreover, Radvansky's principles for ascribing situational models to experiments appear to be post hoc ways of redescribing the data. On the other hand, the evidence does support the Adaptive Control of Thought--Rational (ACT-R) assumption that participants can adjust their attentional weightings and so produce differential fan effects. Moreover, the ACT-R theory of the fan effect is consistent with many other findings.     

Form and content: looking at visual features of television.

Television viewing at home by 50 individuals in 5 age groups (2-, 5-, 8-, 12-year-olds, and adults) was recorded on 1-s time-lapse videotapes over 10-day periods. Coding was based on 5-min point samples. Analysis examined looking at the TV screen in relation to the visual presence of the features cuts, movement, animation, man, woman, child, and nonhuman; content features were child vs. adult programming and overt purposeful character behavior. Cuts, movement, and overt purposeful character behavior were positively related to looking independent of child vs. adult programming. Associations with looking for the remaining features depended on the viewer's age or sex or type of content within which they occurred.