LIFESPAN AND OUTPUT

This paper develops a finite-lifetime continuous-time model of human capital acquisition. Exogenous technological progress has two aspects, a knowledge frontier and an ease-of-learning parameter. We find that as lifespan increases: (1) output per person-hour rises in a concave fashion, and (2) learning during the work-phase of life only occurs when individuals have a sufficiently long lifespan. As a result, countries that differ in the average lifespan of their inhabitants can have permanently different levels of output per person even in the presence of free trade, perfect capital markets and common production functions. ( JEL O33, J24, F43, D91)     

The Role of Statistical Models in the Prediction of Tropical Cyclone Motion

Tropical cyclones (tropical storms, hurricanes, typhoons, etc.) occur over many of the earth's tropical marine areas. Responsibility for tracking and predicting the future course of these storms is assigned to one or more domestic or foreign meteorological services. These services routinely activate a number of statistical and dynamical prediction models as objective guidance preparatory to issuing official forecasts on these storms. In this article, the role of the statistical models in this process is examined.     

Non-Normal Bivariate Distributions with Normal Marginals

The purpose of this note is to indicate that Fieller's Theorem can be expressed in the matrix formulation of the general linear model. The practical consequence is that one general computer program which can estimate the parameters and test the validity of a pertinent model, can also compute confidence limits for the ratios of any linear combinations of the parameters.     

Effects of Political Advertising

Relationships between broadcast advertising exposure and variouscognitive and affective orientations were assessed in a surveyof voters during a congressional election campaign. Exposurewas moderately correlated with political knowledge and interest.Highly exposed voters were somewhat more likely to attach higheragenda priorities to issues and candidate attributes emphasizedin the commercials. Personal affect toward each candidate wasmildly associated with advertising exposure frequency.