Computing equilibria of GEI by relocalization on a Grassmann manifold

An algorithm is described to compute equilibria of the general economic model with incomplete asset markets, that is, of GEI. The algorithm is based on the existence of a route of zeros of a homotopy whose domain includes the price simplex and a Grassmann Manifold. This route is followed, in effect, by localizing and following diffeomorphic pieces in Euclidean space, and by relocalizing as is necessary.     

Research notes and communications management and organizational change: A note on the railroad industry

Hypotheses which relate top-level managers' age, years of company and industry service, and education to strategic change are studied with a sample of 855 managers from 27 railroads. Results generally support hypotheses that younger managers and those with less experience are more likely to alter their strategies with changing environmental conditions.     

Evolutionary Stability in the Investment-Opportunism-Retaliation Game

Can economically efficient outcomes be obtained and sustained in the absence of externally enforced property rights? We study the evolutionary properties of a game that exhibits two well-defined Nash equilibria: one generates an inefficient outcome while the other set generates an efficient outcome supported by the potential for retaliation. Although standard forward-looking refinements eliminate the efficient equilibrium, neither equilibrium type satisfies strict evolutionary stability criteria. However, both types of equilibrium define strategies that are neutrally stable, which makes them vulnerable to drift in dynamic environments. We conduct computer simulation experiments in which players learn adaptively via a tournament selection mechanism called sophisticated experimentation. Our simulations demonstrate that while the system spends a disproportionately high proportion of time in the inefficient equilibrium set, the efficient equilibrium is pervasive as the system drifts back and forth between the equilibrium sets, never settling on one or the other.     

The Financial and Operational Impacts of FERC Order 636 on the Interstate Natural Gas Pipeline Industry

The Federal Energy Regulatory Commission's Order 636 fundamentally altered the regulatory and operational environment of the natural gas industry in 1992, as the culmination of several directives aimed at relaxing regulation and fostering competition. We hypothesize that gas pipeline firms subsequently changed their operational and financial behavior in ways consistent with reduced balkanization, increased competition, and reduced expense preference behavior. Our results indicate that these firms have become more homogeneous financially but less so operationally. We find evidence that the marginal profitability of various pipeline activities has responded more to financial market conditions than to the regulatory environment.     

Labor force migration, non-labor force migration, and non-employment reasons for migration

This paper documents the extent and nature of non-employment factors in migration. The labor force status of over 18 million recent interstate migrants in the United States and stated reasons for moving reported in several surveys in the U.S. are examined. Labor force migrants are heterogeneous in terms of the relationships between acquisition of employment and the migration decision, and in terms of the influence of decision makers outside of the migrant household including firms and the government. Numerically important categories of migrants not traditionally captured in migration models exist, including the elderly, the military, and movers from abroad. Whereas non-employment reasons are secondary to employment reasons for a majority of labor force migrants, non-employment factors are singularly important or operate in combination with employment factors for the majority of all migrants. The heterogeneity of migrant types and migration reasons needs to be better captured in migration models.     

Valuing ecosystem goods and services: a new approach using a surrogate market and the combination of a multiple criteria analysis and a Delphi panel to assign weights to the attributes

A new approach to valuing ecosystem goods and services (EGS) is described which incorporates components of the economic theory of value, the theory of valuation (USappraisal), a multi-model multiple criteria analysis (MCA) of ecosystem attributes, and a Delphi panel of experts to assign weights to the attributes. The total value of ecosystem goods and services in the various tenure categories in the Wet Tropics World Heritage Area (WTWHA) in Australia was found to be in the range AUD$188 to $211 million year⁻¹, or AUD$210 to 236 ha⁻¹ year⁻¹ across tenures, as at 30 June 2002. Application of the weightings assigned by the Delphi panelists and assessment of the ecological integrity of the various tenure categories resulted in values being derived for individual ecosystem services in the World Heritage Area. Biodiversity and refugia were the two attributes ranked most highly at AUD$18.6 to $20.9 million year⁻¹ and AUD$16.6 to $18.2 million year⁻¹, respectively.     

The ‘light touch’ of the Black Death in the Southern Netherlands: an urban trick?

Although the fanciful notion that the Black Death bypassed the Low Countries has long been rejected, nevertheless a persistent view remains that the Low Countries experienced only a ‘light touch’ of the plague when placed in a broader European perspective, and recovered quickly and fully. However, in this article an array of dispersed sources for the Southern Netherlands together with a new mortmain accounts database for Hainaut show that the Black Death was severe, perhaps no less severe than other parts of western Europe; that serious plagues continued throughout the fourteenth and fifteenth centuries; and that the Black Death and recurring plagues spread over vast territories—including the countryside. The previous conception of a ‘light touch’ of plague in the Low Countries was created by the overprivileging of particular urban sources, and a failure to account for the rapid replenishment of cities via inward migration, which obscured demographic decimation. We suggest that the population of the Low Countries may not have recovered faster than other parts of western Europe but instead experienced a greater degree of post‐plague rural–urban migration.     

Value for money in energy efficiency retrofits in Ireland: grant provider and grant recipients

The Sustainable Energy Authority of Ireland (SEAI) administers the Better Energy Homes scheme to provide a financial incentive for home owners to engage in energy efficiency retrofits. This study analyses data from the scheme and Building Energy Rating data for participants to the scheme to examine the value for money achieved by households. In addition, this research identifies which retrofit combinations provide greatest value for money, in terms of energy efficiency gains, for the grant provider. We utilize an error-in-variables approach to model the variation in benefits accruing to households of varying characteristics. We find that household and grant provider surplus can be maximized in the short term by retrofitting less energy efficient and larger homes, timber or steel frame homes and houses rather and apartments. The types of retrofits leading to the greatest surplus for both household and grant provider include cavity wall insulation paired with either a boiler with heating controls or heating controls only retrofit.     

Requests for zoo visitors to undertake pro-wildlife behaviour: How many is too many?

Recognising the potential conservation impact, zoos regularly ask their visitors to undertake pro-wildlife behaviour. This paper presents the results of two studies undertaken to address the question: how often during a visit should visitors be asked? Study 1 sought to a) determine individuals' personal thresholds and b) the point where the number of different behaviours requested began affect visitors' experiences. Study 2 sought the same, but focused on requests for the same behaviour. Results suggest that few respondents' personal thresholds were crossed (2.5% in Study 1 and 9% in Study 2). In neither study did many respondents (2.5% in Study 1 and 2.8% in Study 2) feel that the number of requests negatively affect their overall zoo experience. While there are caveats, we conclude that there appears little cause for concern about asking zoo visitors on multiple occasions to act in support of wildlife. Indeed, such requests may improve experiences.