Nonlinear duration dependence in stock market cycles

We reexamine duration dependence in stock market cycles using a generalized Weibull model. Recent empirical work by Cochran and DeFina [Cochran, S. J., & DeFina, R. H. (1995). Duration dependence in the U.S. stock market cycle: A parametric approach. Applied Financial Economics, 5, 309-318.], who use a chronology of stock market cycles to estimate a Weibull hazard model, shows duration dependence in stock prices. They find evidence of duration dependence in prewar market expansions and postwar market contractions. We update their postwar sample, then use a more flexible model that finds evidence of duration dependence for all prewar and postwar samples. The generalized Weibull model is shown to be statistically superior to the conventional Weibull model for all samples except prewar expansions.     

Rethinking the central institutions of modern society: science and business

A significant part of this issue of Futures is given over to the following presentation by Willis Harman, and a series of responses from prominent futurists—a colloquium, if you like. Harman's paper, written prior to the UN Conference on Environment and Development (UNCED) in June 1992, develops further his argument, made in Global Mind Change and other works. Harman argues that the origins of our current problems lie in the belief system supporting our economic structure. The symptoms will only be healed if our worldview changes. All six respondents find merit in Harman's paper, although not all accept his diagnosis or recommendations.     

On military RDT&E in Israel

Military research, development, testing and evaluation in Israel are described in historical perspective prior to the 1973 war. Emphasis is given to the advantages of short, informal lines of communication, flexibility in the process of weapons development and to the immediacy of perceived military threat as possible reasons for success of weapons developed by or weapons technologies adapted by Israel. Relatively small size of the nation and the military organization are also seen to be advantages for effective development or adoption of military technology.