Some results on moments and cumulants

Abstract

In the present paper we discuss various results related to moments and cumulants of probability distributions and approximations to probability distributions. As the approximations are not necessarily probability distributions themselves, we shall apply the concept of moments and cumulants to more general functions. Recursions are deduced for moments and cumulants of functions in the form R_k [a, b] as defined by Dhaene & Sundt (1996). We deduce a simple relation between the De Pril transform and the cumulants of a function. This relation is applied to some classes of approximations to probability distributions, in particular the approximations of Hipp and De Pril.     

Measures of corruption and determinants of US corruption

This paper contributes to the literature by examining whether conclusions from empirical models of corruption determinants are robust with respect to three alternative measures of corrupt activity for the US states. Are the determinants of US corruption sensitive to the choice of the measure of corruption? Overall, the answer to this question is that the choice of the measure of corruption matters in explaining corruption. However, some findings are robust across measures. For instance, greater educational attainment lowers corruption, while greater judicial employment adds to corruption. Southern states were found to be more corrupt, ceteris paribus. We also provide evidence that it is important to control for enforcement efforts in empirical modeling using convictions as a measure of corruption. Significant differences, however, across corruption measures occur in a number of other instances. Specifically, the effects of urbanization, economic prosperity, population size, media, government spending, and enforcement are sensitive to the measure of corruption. Further, the influences of the nation’s foreign neighbors and of the location of the state relative to the nation’s capital remain unclear.     

Engaging Students in Research: The Use of Professional Dialogue

Graduate students frequently have difficulty defining, developing, and resolving research problems in a manner consistent with the agricultural economics community. We report on a seminar that focuses on professional dialogue to assist graduate students to integrate subject matter courses into independent research proposals. Professional dialogue involves developing arguments to explain and resolve questions where the explanations are supported by warranted evidence and appropriately qualified. The premise of the seminar is that more active problem solvers are developed using professional dialogue to sharpen critical thinking and writing skills.     

Earnings growth and the bull market of the 1990s: Is there a case for rational exuberance?

This paper examines whether permanent earnings growth, crucial to stock valuation, increased during the 1990s, as suggested by proponents of the new economy. Using S&P 500 earnings for the period of 1951–2000, we do not find strong evidence of either a one-time structural break or gradual change. However, the confidence interval on permanent earnings growth is wide enough to include an increase that is roughly consistent with the bull market of the late 1990s. Thus, we cannot reject a rational basis for that exuberance.     

An introduction to evolutionary theories in economics

This paper presents the basic ideas and methodologies of a set of contemporary contributions which are grouped under the general heading of evolutionary economics. Some achievements-especially with regard to the analysis of technological change and economic dynamics-are illustrated, some unresolved issues are discussed and a few promising topics of research are flagged.This article draws on a chapter prepared for the book Market and Organization: The Competitive Firm and its Environment, edited within an EEC/Tempus Programme by LATAPSES, Nice, France, and Iside, Rome.     

The Impact of Securities Litigation Reform on the Disclosure of Forward-Looking Information By High Technology Firms

This study evaluates corporate voluntary disclosure of forward-looking information under the safe harbor provision of the Private Securities Litigation Reform Act of 1995. Using a sample of 523 computer hardware, computer software, and pharmaceutical firms, we find a significant increase in both the frequency of firms issuing earnings and sales forecasts and the mean number of forecasts issued following the Act's passage. To provide more direct evidence that our findings are attributable to the Act reducing firms' legal exposure, we develop a proxy for litigation risk and examine whether the increase in disclosure is more pronounced for firms at greatest risk of a lawsuit. As expected, we find that the change in disclosure is increasing in firms' ex ante risk of litigation. Finally, we report that the safe harbor had no adverse impact on the quality of forward-looking information. Forecast errors, whether directional or non-directional, were not significantly affected by the Act's passage.     

An empirical note from case documents on the economies of network television advertising

Economists have argued for many years about the extent of economies of geographic scope in television advertising. This paper maintains that previous studies could not correctly resolve this issue because they employed list prices, rather than transactions price data. In contrast to previous research, this paper reports transaction based prices from internal company documents. These transaction based data indicate that network advertising was substantially less costly per viewer than equivalent coverage using local spot television advertising. Local firms, unable to use network advertising as did their national competitors, faced high per viewer advertising costs as a result.