Instrumental Variables for Logistic Regression: An Illustration

The estimated effect of a regressor on an outcome is inconsistent when that regressor is determined simultaneously with that outcome. Instrumental variables estimation is a means of obtaining consistent parameter estimates in this situation. The best-known form of instrumental variables is two-stage least squares; unfortunately, this procedure cannot be simply extended to non-linear models such as logistic regression. Instrumental variables estimation, however, is still possible, and using the Generalized Method of Moments, this paper is the first to produce instrumental variables estimates for logistic regression. Obtaining these estimates is easy using widely available software. An illustrative example is provided. This methodology should be useful to social scientists familiar with 2SLS and logistic regression.     

Metabolism, energy, and entropy in Marx's critique of political economy: Beyond the Podolinsky myth

Until recently, most commentators, including ecological Marxists, have assumed that Marx's historical materialism was only marginally ecologically sensitive at best, or even that it was explicitly anti-ecological. However, research over the last decade has demonstrated not only that Marx deemed ecological materialism essential to the critique of political economy and to investigations into socialism, but also that his treatment of the coevolution of nature and society was in many ways the most sophisticated to be put forth by any social theorist prior to the late twentieth century. Still, criticisms continue to be leveled at Marx and Engels for their understanding of thermodynamics and the extent to which their work is said to conflict with the core tenets of ecological economics. In this respect, the rejection by Marx and Engels of the pioneering contributions of the Ukrainian socialist Sergei Podolinsky, one of the founders of energetics, has been frequently offered as the chief ecological case against them. Building on an earlier analysis of Marx's and Engels's response to Podolinsky, this article shows that they relied on an open-system, metabolic-energetic model that adhered to all of the main strictures of ecological economics – but one that also (unlike ecological economics) rooted the violation of solar and other environmental-sustainability conditions in the class relations of capitalist society. The result is to generate a deeper understanding of classical historical materialism's ecological approach to economy and society – providing an ecological-materialist critique that can help uncover the systemic roots of today's “treadmill of production” and global environmental crisis. Paul Burkett is Professor of Economics at Indiana State University, Terre Haute. He is the author of Marx and Nature: A Red and Green Perspective (1999), and the co-author, with Martin Hart-Landsberg, of China and Socialism: Market Reforms and Class Struggle (2005). John Bellamy Foster is Professor of Sociology at the University of Oregon in Eugene, Oregon, and co-editor of Monthly Review (New York). He is the author of The Vulnerable Planet (1994, 1999); “Marx's Theory of Metabolic Rift: Classical Foundations for Environmental Sociology,” American Journal of Sociology (September 1999); Marx's Ecology (2000); Ecology Against Capitalism (2002); and Naked Imperialism (2005).     

Assessing the effectiveness of strategic planning

This paper describes a method for assessing the effectiveness of strategic planning systems in terms of the results actually observed subsequent to planning activity. The paper explains in particular how, in making the assessment, one might cope with the fact of environmental change subsequent to the setting of planned goals. This ends oriented approach to measuring effectiveness is shown to be complementary to process oriented approaches and is illustrated by an example from the coal industry.     

Estimating the costs of preventive interventions

The goal of this article is to improve the practice and reporting of cost estimates of prevention programs. It reviews the steps in estimating the costs of an intervention and the principles that should guide estimation. The authors then review prior efforts to estimate intervention costs using a sample of well-known but diverse studies. Finally, the authors illustrate the principles with an example, the Family Bereavement Program. They conclude that example by discussing whether and how the costs of the intervention might differ when implemented in a real-world setting.     

Estimation of Acute Toxicity by Fitting a Dose-Time-Response Surface

In acute toxicity testing, organisms are continuously exposed to progressively increasing concentrations of a chemical and deaths of test organisms are recorded at several selected times. The results of the test are traditionally summarized by a dose-response curve, and the time course of effect is usually ignored for lack of a suitable model. A model which integrates the combined effects of dose and exposure duration on response is derived from the biological mechanisms of aquatic toxicity, and a statistically efficient approach for estimating acute toxicity by fitting the proposed model is developed in this paper. The proposed procedure has been computerized as software and a typical data set is used to illustrate the theory and procedure. The new statistical technique is also tested by a data base of a variety of chemical and fish species.     

Mothers and Divorce: Legal,Economic and Social Dilemmas,by Terry Arendell

Becoming an Ex: The Process of Role Exit , by Helen Rose Fuchs Ebaugh. Chicago: University of Chicago Press, 1988, 247 pages.