Demographic transition: A forcing model

Transition Theory provides the theoretical underpinning for many explanations for past population changes and, more importantly, for many population projections. Our paper proves, through the use of symbolic logic, that Transition Theory does not contain principles strong enough to support population projections. Such projections, consequently, must be based upon their author's intuition rather than a reasoned application of Transition Theory. We follow our proofs with a brief discussion of various ways in which the Theory may be modified. Our emphasis is upon and only upon the logical characters of these modifications.     

Limousine Liberals and Corporate Conservatives: The Financial Constituencies of the Democratic and Republican Parties*

Objective. This study examines the backgrounds, political attitudes, issue preferences, and political participation of congressional donors who contribute $200 or more to congressional campaigns. Methods. We use a nationwide survey of more than 1,000 donors and analyze differences among these individuals using cluster analysis. Results. Although these significant donors are economic elites, we find they are not monolithic in their political views and attitudes. There are significant cleavages in the donor pool across and within the two major parties on various political issues and involvement in different political organizations. Perhaps most important, we find that the most active donors hold the most ideologically extreme political views. Conclusions. The results suggest that the sharp cross‐party differences and the meaningful variations within party coalitions, combined with the greater activity of more ideologically extreme donors, contribute to and reflect party polarization.     

Comparing J independent groups with a method based on trimmed means

The ANOVA-F test is the most popular and commonly used procedure for comparing J independent groups. However, it is well known that this method is very sensitive to non-normality, which has led to the derivation of alternative techniques based on robust estimators. In this work, ANOVA-F-test, trimmed mean Welch test, bootstrap-t trimmed mean Welch test, Schrader and Hettmansperger method with trimmed means, a percentile bootstrap method with trimmed means and a newly proposed method were compared in terms of both the Type I error probability and power. The proposed method compares well with ANOVA-F and other alternatives under various situations.