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61.
This study shows that firms in the pharmaceutical industry experience decreasing returns to scale in R & D as the level of R & D expenditures rises. The paper presents the results of our study of the innovative output of 16 pharmaceutical firms over a 19 year period. Given the strong correlation between R & D budgets and firm size, our study suggests the wave of mergers in the industry may yield less innovative productivity than managers expect.  相似文献   
62.
Received March 5, 2001; revised version received August 5, 2002 Published online: April 30, 2003  相似文献   
63.
In this paper, we seek to empirically assess which determinants of the capability and incentives of banks to screen and monitor firms are significant in explaining credit rationing to Italian SMEs. After testing for the presence of non‐random selection bias and the potential endogeneity of some determinants of interest, the probit model results we obtain suggest that the average banking size and the multiple banking relationship phenomenon are statistically significant factors affecting credit rationing, presumably through their impact on the aforementioned banks' capability and incentives. Other potential determinants of banks' incentives to monitor and screen, such as local banking competition and firm' capacity to collateralize, are never significant. However, when we split the sample according to the level of competition in credit markets, we find that the estimated marginal effects of all significant determinants of interest are larger in absolute value than those obtained when using the whole sample.  相似文献   
64.
65.
The general design for the real-time electricity market presented in this paper optimizes and prices both real and reactive power simultaneously in an AC setting, where all assets—generation, load and transmission—are allowed to bid and are financially settled at the locational price times energy consumed or produced. The result is that transmission lines are compensated for both capacity and admittance, providing incentives for efficient operation of transmission-related assets such as FACTS devices, if price-taking behavior is assumed. Losses are incorporated into the design and become an operating cost for transmission. The market design is shown to be revenue neutral and, under some assumptions, nonconfiscatory.   相似文献   
66.
Graphical models provide a powerful and flexible approach to the analysis of complex problems in genetics. While task-specific software may be extremely efficient for any particular analysis, it is often difficult to adapt to new computational challenges. By viewing these genetic applications in a more general framework, many problems can be handled by essentially the same software. This is advantageous in an area where fast methodological development is essential. Once a method has been fully developed and tested, problem-specific software may then be required. The aim of this paper is to illustrate the potential use of a graphical model approach to genetic analyses by taking a very simple and well-understood problem by way of example.  相似文献   
67.
68.
The United States (US) exports more than US$6 billion in agricultural commodities to the European Union(EU) each year, but one issue carries the potential to diminish this trade: use of biotechnology in food production. The EU has adopted more stringent policies towards biotechnology than the US. Understanding differences in European and American policies towards genetically modified (GM) foods requires a greater understanding of consumers’ attitudes and preferences. This paper reports results from the first large‐scale, cross‐Atlantic study to analyse consumer demand for genetically modified food in a non‐hypothetical market environment. We strongly reject the frequent if convenient assumption in trade theory that consumer preferences are identical across countries: the median level of compensation demanded by English and French consumers to consume a GM food is found to be more than twice that in any of the US locations. Results have important implications for trade theory, which typically focuses on differences in specialization, comparative advantage and factor endowments across countries, and for on‐going trade disputes at the World Trade Organization.  相似文献   
69.
Arguments about the existence of the so-called energy efficiency gap are typically based on evaluations of efficiency measures as investments whose end result is to reduce the cost of providing a given level of energy services. This article demonstrates that the investment approach tends to undervalue energy efficiency improvements because it omits the increase in utility that results from the consumer's substitution of energy services for other goods. The substitution occurs because the efficiency measure reduces the marginal cost (implicit price) of energy services. Sample calculations based on a Cobb-Douglas utility function are used to illustrate the potential size of the undervaluation of efficiency investments.  相似文献   
70.
This paper addresses two very old issues in human society: espionage and double crossing. Our major conclusion points out that there will be a serious over rewarding problem in the direct mechanism due to double crossing in espionage, and a competitive mechanism with a relative performance regime can possibly mitigate the over rewarding problem and still extract the information.   相似文献   
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