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51.
The historic focus of new products research has been on the ability of new products to enhance the profitability and competitive position of the innovating firm. In this article, Timothy Devinney shows that there exists an overlooked and potentially significant side effect associated with new product innovations: financial risk changes. He reports that significant financial risk changes occurred in approximately 50% of the new product announcements he examined. The magnitude of these financial risk changes translates into overestimates or underestimates of the firm's cost of capital by 17% to 18% and is strongly and positively related to the size of the firm and the firm's new product innovation activity.  相似文献   
52.
In this paper we analyze the properties of price equilibria in a duopoly market where firms sell vertically differentiated products, consumers being uncertain about which firm sells which quality. Both existence and properties of price equilibria are characterized by the beliefs of the consumers' population about the distribution of quality between firms.  相似文献   
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The price movements of certain assets can be modeled by stochastic processes that combine continuous diffusion with discrete jumps. This paper compares values of options on assets with no jumps, jumps of fixed size, and jumps drawn from a lognormal distribution. It is shown that not only the magnitude but also the direction of the mispricing of the Black-Scholes model relative to jump models can vary with the distribution family of the jump component. This paper also discusses a methodology for the numerical valuation, via a backward induction algorithm, of American options on a jump-diffusion asset whose early exercise may be profitable. These cannot, in general, be accurately priced using analytic models. The procedure has the further advantage of being easily adaptable to nonanalytic, empirical distributions of period returns and to nonstationarity in the underlying diffusion process.  相似文献   
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Summary A sequential testing procedure called 2-SPRT for the meanμ of the negative binomial distribution with known exponentk is presented. For any fixedμ 0(μ 1<μ 0<μ 2), the 2-SPRT provides an asymptotic solution to the modified Kiefer-Weiss problem. Determination ofμ 0 such that the test provides an approximate solution to the Kiefer-Weiss problem is described. The behavior of the 2-SPRT and the Sequential Probability Ratio Test is investigated using Monte Carlo methods. The error probabilities and the average sample numbers are compared. All the computations were carried out on the Alabama Supercomputer.  相似文献   
57.
Dr. M. Riedel 《Metrika》1992,39(1):209-217
Summary In this note we characterize all linear transformations of random vectors which are invariant for a given parametric covariance family. Two one-dimensional covariance families are discussed in detail.  相似文献   
58.
A growing awareness of workplace hazards and identification of airborne contaminants, coupled with a changing safety and health regulatory environment, created an unexpected demand for new and innovative respirators in the early 1980s. 3M's Occupational Health and Environmental Safety Division broke new ground by taking the team concept further than ever before in the company. The division's Action Teams successfully designed, built and introduced products in less than half the time it would have taken previously. Robert Hershock, Charles Cowman and Douglas Peters describe how 3M learned important lessons about team selection, training, performance and motivation, the importance of project sponsors, and the role of middle management.  相似文献   
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Atlanta has the reputation of being a city of opportunity for blacks. However, in Atlanta, as well as in other cities across the nation, the nexus of racism and economic discrimination has resulted in disparities between the housing status of blacks and whites. This article examines racial disparities in the Atlanta housing market. It begins by tracing recent trends in the Atlanta-area economy and by providing background information on the local housing market. It then discusses the roles of the federal Home Mortgage Disclosure Act of 1975 and Community Reinvestment Act of 1977 in the efforts of local groups to reduce racial disparities in the housing market. The final section discusses recent local developments that might lead to improvements in the housing status of black Atlantans.  相似文献   
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