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1.
The corporate diversification literature presents a puzzle. Short-horizon event studies report positive abnormal returns around the announcement of a diversifying event, while studies that examine diversified firms find evidence that diversified firms are worth less than specialized firms (a diversification discount). If diversification is value destroying, perhaps the destruction occurs over longer periods than have been previously tested. This paper tests the hypothesis that diversifying firms have negative long-run abnormal performance following diversification by examining a sample of specialized firms that have a diversifying event from 1978 through 1998. The firms are tracked for up to five years past their diversification year. There is evidence that value is destroyed for small firms that diversify but enhanced for larger firms that diversify.
David C. HylandEmail:
  相似文献   
2.
We consider whether disaggregated data enhance the efficiency of aggregate employment forecasts. We find that incorporating spatial interaction into a disaggregated forecasting model lowers the out-of-sample mean squared error from a univariate aggregate model by 70% at a two-year horizon.  相似文献   
3.
    
Modern tools for cost-effective conservation reserve site planning require the planner to have information about spatial distributions of conservation costs and benefits. Climate change creates unprecedented uncertainty about future land values and species habitat ranges, such that conservation scientists cannot map costs and benefits with certainty anymore. This paper contributes to the literature on the economics of conservation in the face of climate change uncertainty. It advances a new method for using modern portfolio theory to choose lands to protect that yield total conservation returns with less uncertainty. It explores the implications for portfolio recommendations of variation in the correlations between ecological and land-value responses to climate change. It also tests the robustness of the method to shortcuts that might be taken to simplify analysis, identifying problems that arise if conservation costs are ignored in portfolio analysis and demonstrating when portfolio recommendations are sensitive to how ecological benefits are quantified.  相似文献   
4.
Voting referenda provide direct evidence of the demand for public goods. A number of previous studies have used referenda to analyze the support for public environmental goods. These studies have used aggregate data from large jurisdictional units (usually counties) and summary income measures such as the mean or median, and have usually found that higher income areas offer greater support for environmental propositions. We examine environmental referenda voting in California using census block group data, spatial dependence controls, and detailed income distribution data. We find that household income has a negative marginal effect on environmental referenda voting for most of the income range when using census block data. In addition, controls for spatial dependence significantly reduce the magnitude of most coefficients. This suggests that OLS estimates of referenda determinants are biased. We also show that county level data may be subject to severe aggregation bias and might not be appropriate for referenda studies.  相似文献   
5.
西部大开发战略的实施 ,为武汉这个中部特大中心城市的发展提供了机遇 ,如何顺势起飞 ,关键在于武汉中心城市功能的发挥。处于中部承东启西 ,九省通衢 ,基础强劲的武汉特大中心城市功能的发挥 ,也会有力地促进西部大开发战略的落实。武汉立足于其区位综合优势 ,从集散功能、生产功能、管理功能、服务功能、创新功能发展出发 ,借西部大开发之势重构和强化其金融商贸中心功能、交通枢纽功能、通讯信息中心功能、科技教育文化中心功能、生产和服务中心功能 ,是武汉发展和西部大开发的双赢策略。  相似文献   
6.
The objective of this article is to study the interactions that exist between public research and private research in the French biotechnology sector. These interactions are observable at a double level. On the one hand, public research can influence private research, and conversely. Researchers of these two spheres develop important relations of cooperation. We then seek to identify these mutual influences and to measure their spatial dimension. Using asymptotic least squares method, we show that spillovers can diffuse through cooperation in upstream and downstream phases of the innovation process. On the other hand, spillovers resulting from public or private research, when measured by an external stock of knowledge, would be located, in so far as they exist.  相似文献   
7.
    
In this study, we analyze the regulation of markets for the provision of services whose costs are subsidized for paternalistic reasons. We model the choice of a benevolent regulator who wants to maximize consumer welfare in a setting where quality cannot be verified and the good provided is fully subsidized. The choice is thus made between two types of providers (profit maximizers and altruistic providers) and two frameworks (monopoly franchise and quality competition). Our analysis shows that in this environment the performance of mixed markets is always dominated by pure forms. Moreover, although making efficient providers compete for the market minimizes cost, the choice of quality competition with altruistic providers may be preferable from a welfare point of view whenever service quality is relevant and the productivity differential is not substantial.  相似文献   
8.
In the Greater Mumbai Region (GMR), jobs and housing are agglomerating in nodes in the periphery of Mumbai City. However, current transportation investments focus on strengthening connections within Mumbai City, while these outlying nodes have received less attention. As housing and jobs move out, given limited travel choices, the need for mobility nudges many middle class Indian households into owning private vehicles. Using household travel survey data from the GMR, this paper develops an understanding of how worker’s trips are different for those who commute to the city versus the exurbs. Socio-economic and transportation indicators for middle class workers going to the city versus the exurbs show that these populations are quite similar demographically. However, those traveling to the exurbs, on average, tend to be at a socio-economic disadvantage with respect to income, education and out-of-pocket travel burdens. Those traveling to exurban work locations have shorter travel times and trip distances, and make much higher use of walking, biking, rickshaws, and motorized two-wheelers compared to commuters to Mumbai City. Across the GMR, car users travel longer and farther compared to motorized two-wheeler users. On average, traveling by a private vehicle is faster than bus or rickshaw travel revealing advantages of private vehicle use. These mode choices in the middle class have resulted in rapid motorization and negative externalities such as traffic congestion and emissions. Evidence of large increases in motorized two-wheelers and cars in India suggests that these modes will likely keep growing, unless competing efficient travel options are supplied.  相似文献   
9.
This paper proposes an accessibility-based spatial mixed logit (SML) model with panel data structure to examine the impacts of High-Speed Rail (HSR) on land cover change in large urban areas. Using data between 1990 and 2006, impacts of the Spanish HSR on Madrid’s Atocha railway station influence area – a 20 km radius buffer centred on the station – were investigated. To model the HSR impacts, besides socioeconomic variables, the development of both local and regional transportation networks with corresponding accessibility improvement is also taken into account to segregate the impacts of land-cover change brought by different sources of accessibility measures. In this study, two SML models are used: one incorporates regional accessibility indicators as a base model, and the other does not, acting as a control model. The model estimation results reveal that the reduction of the local and regional weighted travel average time has positive impacts on the Atocha station catchment area’s urbanised land-cover rates. Although the base and control models both achieve high goodness-of-fit values, the base model that considers regional accessibility reveals a better goodness-of-fit statistic and is more robust than the control model. It is concluded that the improvement of regional accessibility due to the arrival of HSR at Atocha station plays an essential role in the urbanisation of land cover changes in the study area.  相似文献   
10.
    
Nonhub airports are an essential component in the National Plan of Integrated Airport Systems (NPIAS) of the United States in that they connect regional towns and small communities to the air transportation network. Understanding the interplay of operational and spatial factors in determining average passenger yield of nonhub airports provides airlines with valuable information for network planning and revenue management. This study examines factors contributing to the yield variation among nonhub airports in the U.S. Using ordinary least squares (OLS) based econometric models, this study captures the spatial dependence of passenger yield of nonhub airports, which tends to increase with a corresponding increase in distance to the nearest large hub airport. Nonhub airports surrounding large hub airports with higher passenger enplanements and higher average yields also have higher yields than other nonhub airports. In addition, this study finds the effect of Allegiant Airlines in lowering the average passenger yield of the nonhub airports served directly by the airline, which can be termed as ‘Allegiant Effect’. Findings of this study could provide valuable guidance for airlines to analyze network planning strategies and to identify future markets for growth and for policymakers when allocating resources to communities relying on these nonhub airports.  相似文献   
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