A necessary and sufficient formula for matric factoring

For the purpose of extracting factors from matrices, it is proved that a certain formula is both necessary and sufficient. In factor analysis, the formula may be applied either to the correlation matrix, or directly to the score matrix (assuming the communality problem is solved). As many factors as desired can be extracted in one operation. Having such a compact formulation is useful for teaching as well as computing purposes, since it includes all techniques of factor extraction as special cases.On leave from the Israel Institute for Applied Social Research. This research was facilitated in part by a grant from the Lucius N. Littauer Foundation to the American Committee for Social Research in Israel, Inc.     

Drugs,Sex, and Condoms: Identification and Interpretation of Race‐Specific Cultural Messages Influencing Black Gay and Bisexual Young Men Living with HIV

Black gay and bisexual young men carry a disproportionate burden of HIV in the United States. This study explored Black gay and bisexual young men living with HIV's identification and interpretation of race‐specific cultural messages regarding substance use, sexual activity, and condom use. A total of 36 Black gay and bisexual young men living with HIV (ages 16–24, mean = 20.6 years) from four geographically diverse regions of the United States participated in qualitative in‐depth interviews. Results from this study elucidate the ways in which these young men interpret various forms of race‐specific cultural messages and experiences regarding substance use, sexual activity, and condom use. Participants discussed cultural messages and experiences promoting and discouraging condoms and substance use. Regarding sexual activity, only messages and experiences promoting sex were reported. Across all three categories, messages and experiences promoting risk were predominant. Data further revealed that socially transmitted cultural messages received by young men emanated from multiple sources, such as family, peers, sexual partners, community/neighborhood, and the broader society. Race‐specific cultural messages and experiences should be addressed in interventions for this population, and programs should assist young men in developing a critical consciousness regarding these messages and experiences in order to promote health and well‐being.     

Case illustration: Moving along…and,is change gradual or sudden?

A sequence of analytic sessions of a professional woman in her forties is used to illustrate the moving along process. The material shows a gradual change, where the patient's experience of her sense of agency is altered through a particular kind of interactive sequence. The example is intended to make it clear that the group's view of how change occurs is not strictly or primarily in terms of sudden changes, and that the problem of assessing moments of meeting as well as quantitative and qualitative shifts is one with which the group continues to struggle. © 1998 Michigan Association for Infant Mental Health     

Positive aspects of caregiving as a moderator of treatment outcome over 12 months

The authors examined the influence of positive aspects of caregiving (PAC) as a moderator of treatment outcome across 12 months in 1 of the original sites of the Resources for Enhancing Alzheimer's Caregiver Health I project. They used multilevel random coefficients regression analysis to predict time-varying PAC, depression, behavioral bother, and daily care burden in Alzheimer's caregivers (N = 243; mean age = 60.89, SD = 14.19). They found that time-varying PAC was predicted by time-varying daily care burden. They also found significant effects of time-varying PAC for depression, behavioral bother, and daily care burden. Notably, a PAC x Phase x Treatment effect was found for daily care burden, such that individuals who endorsed less PAC benefited most from the intervention across 12 months. The tendency to positively appraise the caregiving experience (i.e., PAC) in response to chronic stressors such as Alzheimer's caregiving may affect individuals' responsiveness to, and benefit from, interventions, whereas only daily care burden affected the tendency to find enjoyment in caregiving across 12 months. Future intervention research should assess individual PAC in order to better tailor interventions to caregiving needs.     

Effect of imagined movement speed on subsequent motor performance

Researchers realize that motor imagery (MI) duration is closely linked to actual motor action duration. In 2 experiments, the authors investigated the effect of changing MI speed on actual movement duration over a 3-week training period. Experiment 1 involved 2 series of body movements that 24 participants mentally performed faster or slower than their actual execution speeds. The fast MI group's actual times decreased on subsequent performance. Participants in Experiment 2 were 21 skilled athletes who increased (decreased) their well-rehearsed actual movement times after MI training at a slow (fast) speed. The effect was task-related, however: MI affected only self-initiated movement. The effect of MI on actual speed execution supports the ideomotor theory because anticipation of sensory consequences of actions is mentally represented.