COUNT DATA REGRESSION USING SERIES EXPANSIONS: WITH APPLICATIONS

A new class of parametric regression models for both under- and overdispersed count data is proposed. These models are based on squared polynomial expansions around a Poisson baseline density. The approach is similar to that for continuous data using squared Hermite polynomials proposed by Gallant and Nychka and applied to financial data by, among others, Gallant and Tauchen. The count models are applied to underdispersed data on the number of takeover bids received by targeted firms, and to overdispersed data on the number of visits to health practitioners. The models appear to be particularly useful for underdispersed count data. © 1997 John Wiley & Sons, Ltd.     

The Differential Impact of Accurate Product Cost Information in Imperfectly Competitive Markets: A Theoretical and Empirical Investigation*

Many researchers claim that costing systems that provide materially more accurate or precise cost reports have a strict value-enhancing effect on decisions (i.e., Cooper 1988, 1995; Cooper and Kaplan 1991; Christensen and Sharp 1994; Rogers. Comstock. and Pritz 1994; Swenson 1995; Gupta and King 1997). However, this study provides theoretical and empirical evidence that the value of more accurate cost information may be dependent upon the firm's competitive market structure, as well as the firm's product market strategy. We extend the theoretical work of Gal-Or 1986 to incorporate an endogenous imprecise cost signal in two imperfect market structures: Cournot competition and Bertrand competition with imperfectly substitutable products. In addition, we theoretically link market structure to product market strategy. To examine product market strategy, we employ a laboratory markets design that allows for strategic reaction by a rival firm in each of these markets, because the competitive position of a firm is determined by its capacity to produce at low cost, or to differentiate its product from other products (Porter 1985). Consistent with our theoretical work, we argue that firms that compete on the basis of cost leadership (which we demonstrate may be characterized as Cournot competition), benefit through increased profits from increased product cost accuracy, whereas firms that compete on the basis of product differentiation (which we demonstrate may be characterized as Benrand competition) do not benefit from such increased product cost accuracy. Our results are consistent with this contention. That is, profit is higher in the experimental cost leadership markets (operationalized as Cournot markets) when subjects know their true cost, while profit is higher in the experimental product differentiation markets (operationalized as Bertrand markets) when subjects receive uninformative cost reports and make their decisions based on expected costs. These results suggest that the value of more accurate cost reports may be dependent upon the firm's competitive market structure strategy and product market strategy.     

It's the Economy Stupid: Macroeconomics and Federal Elections in Australia

In this paper we examine the impact of macroeconomic conditions on Federal electoral performance in 20th-century Australia. We find that the electorate penalizes a government for high inflation and high unemployment relative to trend. Real GDP growth and real wage growth were not found to have a systematic relationship with incumbent vote share at the Federal level. We also examine the voteshare of the Federal incumbent in three electorates: the safe Liberal seat of Kooyong, the safe Labor seat of Melbourne Pans, and the swinging seat of Latrobe. We find some evidence that unemployment affects electoral outcomes in the swinging seat, but no macroeconomic variables affect outcomes in the safe seats.     

ENVIRONMENTAL POLICIES OF MAJOR COMPANIES: AUSTRALIAN EVIDENCE

In the world-wide literature on business and the environment, the development of a Corporate Environmental Policy (CEP) is seen as an important step in becoming environmentally aware. Australian companies have been found to be developing CEPs, and this study investigates some of the major influences on them to do so. Environmental law appears to be the most persuasive mechanism in the greening of companies. CEPs also appear to be increasingly structured and many appear to contain a statement of objectives which supports the first element of the general framework developed by Grayet al. (1987) for social (environmental) reporting.     

The effect of water hardness on washing performance of built and unbuilt surfactants

Five different surfactants were used at 2.0% concentrations. The most and least effective were found to be Synthrapol N and Ahcowet RS respectively; based on their rating of whiteness index. Synthrapol N and Ahcowet RS were evaluated with the addition of sodium carbonate, sodium tripolyphosphate and a 1:1 combination of the two builders. In both cases the addition of a builder improved the cleaning efficiency of the surfactant. Although each builder alone improved the cleaning efficiency, the combination of sodium carbonate and sodium tripolyphosphate improved efficiency at a lower total concentration.