Air pollution-mortality models: A demonstration of the effects of random measurement error

Errors of measurement have long been recognized as a chronic problem in statistical analysis. Although there is a vast statistical literature of multiple regression models estimating the air pollution-mortality relationship, this problem has been largely ignored. It is well known that pollution measures contain error, but the consequences of this error for regression estimates is not known. We use Lave and Seskin's air pollution model to demonstrate the consequences of random measurement error. We assume a range of 0% to 50% of the variance of the pollution measures is due to error. We find large differences in the estimated effects on mortality of the pollution variables as well as the other explanatory variables once this measurement error is taken into account. These results cast doubt on the usual regression estimates of the mortality effects of air pollution. More generally our results demonstrate the consequences of random measurement error in the explanatory variable of a multiple regression analysis and the misleading conclusions that may result in policy research if this error is ignored.     

Structural instability of the core

Let σ be a q-rule, where any coalition of size q, from the society of size n, is decisive. Let w(n,q)= 2q-n+1 and let W be a smooth ‘policy space’ of dimension w. Let U(W)^N be the space of all smooth profiles on W, endowed with the Whitney topology. It is shown that there exists an ‘instability dimension’ w^*(σ) with 2w^*(σ)w(n,q) such that:

1. (i) if ww^*(σ), and W has no boundary, then the core of σ is empty for a dense set of profiles in U(W)^N (i.e., almost always),

2. (ii) if ww^*(σ)+1, and W has a boundary, then the core of σ is empty, almost always,

3. (iii) if ww^*(σ)+1 then the cycle set is dense in W, almost always,

4. (iv) if ww^*(σ)+2 then the cycle set is also path connected, almost always.

The method of proof is first of all to show that if a point belongs to the core, then certain generalized symmetry conditions in terms of ‘pivotal’ coalitions of size 2q−n must be satisfied. Secondly, it is shown that these symmetry conditions can almost never be satisfied when either W has empty boundary and is of dimension w(n,q) or when W has non-empty boundary and is of dimension w(n,q)+1.     

PROPRIETORIAL CONTROL IN FAMILY FIRMS: SOME FUNCTIONS OF 'QUASI-ORGANIC' MANAGEMENT SYSTEMS

The purpose of this paper is to investigate the strategies of managerial control which are used by the proprietors of family-owned business enterprises. Interviews with the proprietors and senior managers of businesses in the building industry illustrate the ‘quasi-organic’ nature of management structures. These grant some autonomy to senior managers without threatening proprietorial decision-making prerogatives. Although the family firm has certain distinctive features, similar control strategies designed to ensure that delegated decisions are ‘reliable’ and ‘responsible’ are evident in various types of business enterprise. There is, then, scope for further comparative research within a conceptual framework which does not entirely divorce the family firm from other business organizations.     

Income Inequality and Macroeconomic Volatility: An Empirical Investigation

We explore the impact of macroeconomic volatility on the distribution of income. Using a cross‐section of developed and developing countries, we find that greater output volatility, defined as the standard deviation of the rate of output growth, is associated with a higher Gini coefficient and income share of the top quintile. The coefficients suggest that a strong effect on inequality resulting from a reduction in volatility: the Gini coefficient of a country like Chile would fall by 6 points if it were to reduce its volatility to the same level as Sweden or Norway. Our results seem not to be driven by the high‐inequality/high‐volatility Latin American countries.     

Finding a Nash equilibrium in spatial games is an NP-complete problem

Summary. We consider the class of (finite) spatial games. We show that the problem of determining whether there exists a Nash equilibrium in which each player has a payoff of at least k is NP-complete as a function of the number of players.Received: 15 September 2002, Revised: 9 March 2003, JEL Classification Numbers: C72.Correspondence to: H. HallerWe thank a referee for helpful comments. The hospitality of the Institute of Economics, University of Copenhagen, and the Institute for Advanced Studies, Vienna, is gratefully acknowledged by the third author.     

Asymmetric FDI and tax-treaty bargaining: theory and evidence

Tax treaties are often viewed as a mechanism for eliminating tax competition, however, this approach ignores the need for bargaining over the treaty's terms. This paper focuses on how bargaining can affect the withholding taxes set under the treaty. In a simple framework, we develop hypotheses about patterns in treaty tax rates. A key determinant for these patterns is the relative size of bilateral foreign direct investment (FDI) activity. In plausible situations, more asymmetric countries will negotiate treaties with higher tax rates. This theory is then tested using 1992 data from US and Organization for Economic Cooperation and Development (OECD) bilateral tax treaties. Overall, the data supports the prediction that greater asymmetric FDI activity increases the negotiated tax rates.     

Entry and Exchanges of Cost Information

The literature on exchanges of information has ignored firms' entry decisions. Yet, the Federal Trade Commission recently expressed concerns that exchanges of information in business-to-business electronic platforms would adversely impact entry and, thus, consumers. When entry decisions are endogenized in a competitive Cournot model with cost uncertainty, we find results that contrast sharply with current thinking on the welfare consequences of information sharing.     

Late entry,market shares and competitive survival: The case of synthetic fibers

This paper examines product policy in relation to the experience curve and product life cycle concepts in the context of the experience of the thirteen major firms in the Western European synthetic fibers industry. It examines the hypothesis based on Boston Consulting Group and the Profit Impact of Market Share (PIMS) evidence that late entrants to a market will be at a competitive disadvantage because they lack the accumulated experience of the pioneering firms. For each of the three main synthetic fibres, acrylic, nylon and polyester, it was found that the early entrants who established major market shares early in the growth phase of the product life cycle were able to maintain that leadership nearly twenty years later. In contrast not only did almost all the late entrants fail to achieve significant market shares but in the difficult market conditions between 1974 and 1981 they provided seven out of nine market withdrawals.     

The Effects of local Fair Housing Ordinances on Housing Segregation: Their Impact Is Small, But It's an Important Positive Change Toward Integration

Abstract . State and local fair housing ordinances, patterned after federal legislation, are promoted by federal policy. This study investigates whether these local laws have had any effect on levels of residential segregation between Whites and Blacks, 1970-1980, by comparing changes in segregation for 111 cities characterized by different types of fair housing coverage. Results show average declines of 9 points in the index of dissimilarity, with cities covered by both state and local laws declining slightly more than cities with no fair housing coverage. Declines are not greater in cities with laws that are “substantially equivalent” to Title VIII vs. cities with non-equivalent laws. When changes in segregation were examined by a variety of population, economic and housing variables that may affect segregation change, it was found that local ordinances continue to have a small, but statistically significant effect. This effect varies according to the pattern of segregation change under study; deconcentration of ghetto areas and integration of White areas are not affected by type of local fair housing coverage.