ESTIMATION OF THE CONCENTRATION PARAMETERS OF THE FISHER MATRIX DISTRIBUTION ON 50(3) AND THE BINGHAM DISTRIBUTION ON Sq, q≥ 2

Two procedures are considered for estimating the concentration parameters of the Fisher matrix distribution for rotations or orientations in three dimensions. The first is maximum likelihood. The use of a convenient 1-dimensional integral representation of the normalising constant, which greatly simplifies the computation, is suggested. The second approach exploits the equivalence of the Fisher distribution for rotations in three dimensions, and the Bingham distribution for axes in four dimensions. We describe a pseudo likelihood procedure which works for the Bingham distribution in any dimension. This alternative approach does not require numerical integration. Results on the asymptotic efficiency of the pseudo likelihood estimator relative to the maximum likelihood estimator are given, and the two estimators are compared in the analysis of a well-known vectorcardiography dataset.     

Foster parent perceptions of placement breakdown

The purpose of the study was to describe the perceived causes of placement breakdown by foster parents. Sixty-three foster parents from fifty families were asked to describe their challenges in response to the following question: “What would make you consider ending a foster placement”? The responses to this question were analyzed using multidimensional scaling and cluster analysis, to yield nine themes. Foster parents indicated that they would consider ending a placement if there was a danger to their family, if the child could not adapt to the home or if they could not handle the child's behavior. Participants reported that the complex health needs of a foster child, problems dealing with the foster agency, and several unsuccessful attempts to make the placement work would cause a placement to breakdown. Foster parents also indicated that they would consider ending a placement if their personal circumstances changed, their own health deteriorated, or there was a lack of appropriate external support in place. The results of the study point to gaps in the research on violence in general foster care, foster parent perceptions of contributions to a foster child's transition back to his or her birth family, and the process of foster parent decision-making in cases of placement breakdown.     

Carrières et contradictions en sciences de la vie : réponses du corps académique aux transformations de la connaissance et de ses utilisations

Drawing on interviews with more than 80 scientists on two university campuses, we create a typology that offers insights into how transformations in the nature and locus of life science innovation influence academic careers and work practices. Our analyses suggest that a strong outcome of increased academic concern with research commercialization is the appearance of new fault lines among faculty, between faculty and students, and even between scientists' interests and those of their institutions. We argue that life science commercialization is driven by a mix of new funding opportunities, changing institutional mandates for universities, and novel research technologies that bring basic research and product development into much closer contact. The rise of patenting and commercially motivated technology transfer on U.S. campuses is altering faculty work practices and relationships, while transforming the criteria by which success is determined and rewards are allocated. Through close analysis of interviews with four researchers who typify a range of academic responses to commercialism, we demonstrate emerging patterns of conflict and agreement in faculty responses to commercial opportunities in the life sciences.     

Attributional Retraining Increases Career Decision-Making Self-Efficacy

This study examined whether 60 college students (41 women and 19 men), grouped according to their career locus of control, were differentially affected by a videotaped career intervention. The intervention was an attributional retraining procedure designed to persuade students to attribute low levels of confidence in making career decisions and career-related failures to a lack of effort. Results indicated that the career decision-making self-efficacy (CDMSE) of students who initially exhibited an external career locus of control significantly increased after the attributional retraining procedure (p < .05), whereas the students who initially exhibited an internal career locus of control demonstrated no significant increase in CDMSE after attributional retraining.     

The ubiquitous angle

Summary.  Previously we used the geometry of n -dimensional space to derive the paired samples t -test and its p -value. In the present paper we describe the 'ubiquitous' application of these results to single degree of freedom linear model hypothesis tests. As examples, we derive the p - and t -values for the independent samples t -test, for testing a contrast in an analysis of variance and for testing the slope in a simple linear regression analysis. An angle θ in n -dimensional space is again pivotal in the development of the ideas. The relationships between p , t , θ , F and the correlation coefficient are also described by using a 'statistical triangle'.     

ASPECTS OF CORRELATION IN BIVARIATE POISSON DISTRIBUTIONS AND PROCESSES

This paper reviews some interesting but scattered results that are known about correlation in bivariate Poisson distributions and processes and presents some new results. A particular concern in both contexts is with results and examples relating to negative correlation.