A Recursive Formulation of the Old Problem of Obtaining Moments from Cumulants and Vice Versa

It seems difficult to find a formula in the literature that relates moments to cumulants (and vice versa) and is useful in computational work rather than in an algebraic approach. Hence I present four very simple recursive formulas that translate moments to cumulants and vice versa in the univariate and multivariate situations.     

Books received

A Wider Perspective Needed Avraham Greenbaum (ed.), Minority Problems in Eastern Europe Between the World Wars, with Emphasis on the Jewish Minority, introduced by Edward Allworth, Hebrew University of Jerusalem, Institute of Advanced Studies. Jerusalem, 1988. pp.viii, 163.

The Jokes of Oppression David A. Harris and Izrail Rabinovich, The Jokes of Oppression: The Humour of Soviet Jews. Northvale, NJ and London: Jason Aronson, 1988. 275pp. $22.50.

A Pleasant Surprise Franti?ek Mi?eje, Revolu?nou Cestou. Spomienky na roky 1938–1948 (On the Path of Revolution: Reminiscences of the Years 1938–1948.) Bratislava: Pravda publishers on behalf of the Institute of Marxism‐Leninism of the Central Committee of the Communist Party of Slovakia, 1988. 232 pp. Illus. Bibl. Index. Kcs 19.00.     

Prediction based classification for longitudinal biomarkers

Assessment of circulating CD4 count change over time in HIV-infected subjects on antiretroviral therapy (ART) is a central component of disease monitoring. The increasing number of HIV-infected subjects starting therapy and the limited capacity to support CD4 count testing within resource-limited settings have fueled interest in identifying correlates of CD4 count change such as total lymphocyte count, among others. The application of modeling techniques will be essential to this endeavor due to the typically non-linear CD4 trajectory over time and the multiple input variables necessary for capturing CD4 variability. We propose a prediction based classification approach that involves first stage modeling and subsequent classification based on clinically meaningful thresholds. This approach draws on existing analytical methods described in the receiver operating characteristic curve literature while presenting an extension for handling a continuous outcome. Application of this method to an independent test sample results in greater than 98% positive predictive value for CD4 count change. The prediction algorithm is derived based on a cohort of n = 270 HIV-1 infected individuals from the Royal Free Hospital, London who were followed for up to three years from initiation of ART. A test sample comprised of n = 72 individuals from Philadelphia and followed for a similar length of time is used for validation. Results suggest that this approach may be a useful tool for prioritizing limited laboratory resources for CD4 testing after subjects start antiretroviral therapy.     

Canadian Campus Smoking Policies: Investigating the Gap Between Intent and Outcome From a Student Perspective

Abstract

Background: Young adults remain the earliest legal target for the tobacco industry. Against this, the existence of smoking policies would appear to offer some protection to students on campus. However, little research has been conducted into the outcomes of such policies from a student perspective. Methods: The authors conducted 8 focus groups at 4 selected Canadian undergraduate campuses to investigate student perceptions and behaviors resulting from campus smoking policies. Results: Results indicated that student smoking behaviors are minimally impacted by campus smoking policies due to seriously compromised implementation and enforcement. Conclusions: These findings imply that the presence of campus smoking policies and claims of “smoke-free” campuses should not be misinterpreted as achievement and without renewed focus and adequate tobacco control infrastructure, it will remain possible for young adults to initiate and maintain tobacco smoking on campus.     

Determining the effects of intraclass correlation on factorial experiments

This paper considers the effects of the presence of eqmi-correlation between observations in a k-way factorial experiment, A technique to provide unbiased F-tests is also constructed.     

Ethical dilemmas in a professional service context

This paper reports on the results of action research exploring the kinds of ethical problems that confront employees in the professional services industry. Data were collected from a single firm via participant observation methods at eight locations across the country. Issues raised included service delivery, responses to life threatening situations, marketing, client relationships, client entertaining, bribery, billings, as well as intra-firm issues such as support for professional judgments in the field, employee health and safety, and compensation. The paper concludes with an assessment of the utility of the approach taken by the firm, the generalizability of the issues beyond the single case setting, as well as an assessment of the managerial issues related to fostering and sustaining an ethical environment within a business organization.