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71.
72.
Timothy M. Devinney 《Journal of Product Innovation Management》1992,9(3):222-231
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
73.
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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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
79.
James H. Stock 《Oxford bulletin of economics and statistics》1996,58(4):685-701
This paper focuses on the construction of forecasts over long horizons where a typical long-horizon forecast might span four years using 20 to 40 years’ data. It is argued that the presence of persistence in the form of unit or near-unit autoregressive roots poses substantial difficulties for long-horizon interval and point forecasting. These difficulties may not be overcome even by efficient pre-testing or model-selection procedures and might, in general, lead to point forecasts with large asymptotic root mean squared errors and undesirably wide prediction intervals. 相似文献
80.
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