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71.
Rudy Moenaert, William Souder, Arnoud De Meyer, and Dirk Deschoolmeester report the results of their study of forty technologically innovative Belgian companies to examine the interaction between marketing and R&D. They studied one commercially successful and one commercially unsuccessful technological product innovation project in each participating company and collected data from one marketing and one R&D respondent per project. Communication flows between marketing and R&D are increased under conditions involving formalization of projects, decentralization, positive interfunctional climate, and role flexibility.  相似文献   
72.
Improving the quality of Indonesia's coffee exports has been a priority of government and the Association of Indonesian Coffee Exporters for some years. Efforts to achieve this objective have, however, been hampered by misconceptions about the reasons why coffee producers and traders at each point in the marketing network do not deliver a higher quality product. The research reported here shows that price premia for higher quality coffee are not large enough to encourage greater quality enhancement. The world market for low to medium grades, used in the production of instant coffee, is much larger than that for high-quality coffee, and this preference is transmitted in the form of low incentives to improve the product. Failure to understand this has led to government policies which at best do not solve the quality problem and at worst exacerbate it.  相似文献   
73.
Models for which the MLE and the conditional MLE coincide   总被引:1,自引:0,他引:1  
The MLE, CMLE and MMLE coincide in a linear regression model with fixed individual effects. In this case, there is no incidental parameters problem and the MLE is consistent. The equivalence of these estimators is important because CMLE=MLE implies both the consistency of the MLE and the efficiency of the CMLE. In general, we cannot expect to find a CMLE or MMLE, since there may be no fixed-dimension sufficient statistic for the effects, nor an appropriate transformation of the data whose distribution does not depend on the effects. However, we show that the MLE, CMLE and MMLE do coincide in systems of seemingly unrelated regressions and in systems of simultaneous equations. We establish this result for systems in which (exogenous) variables in addition to (or other than) the intercept may have coefficients which vary over individuals, provided that the set of such variables is the same in every equation.The financial support of the National Science Foundation is gratefully acknowledged.  相似文献   
74.
This paper is concerned with one central question: the choice between theories, and the role played by data in that choice. It deals with the uses economists may make of data and the importance of understanding the institutional basis that gives rise to the data - an area in which labour economists have traditionally been particularly strong - and with the relevance of assumptions. It deals with the ultimate need to choose between competing theories (despite the role of conventionalism) on the basis of data rather than retreating into a comfortable 'methodological pluralism'. It considers the role of test replication, with reference to the practice in natural science (and its role there in checking scientific fraud) and concludes that, despite extensive technical problems of testing, economists have to accept a data check if the rhetoric of mathematical technicality is not to overwhelm the need to explain. Parallels are drawn with experience in physics (and the implications of the development of Chaos and Catastrophe for a naively predictionist view are noted), medicine and history (of which, it is argued, modern economists are far too neglectful).  相似文献   
75.
The feminization of poverty refers to female householders and their children becoming an increasing percentage of the poor population. After examining effects of race on poverty of female-headed households from 1959 to 1989, this study investigates statistical relationships among female poverty, economic and labor market conditions, and transfer payments (specifically AFDC) by means of the Granger causality test over the period from 1966 to 1988. This study reinforces the plausible assumption that policies which would lower the unemployment rate of females and would increase real economic growth could be expected to reduce the number of poor female households.  相似文献   
76.
Our examination of the cross-section of expected returns reveals economically and statistically significant compensation (about 6 to 9 percent per annum) for beta risk when betas are estimated from time-series regressions of annual portfolio returns on the annual return on the equally weighted market index. The relation between book-to-market equity and returns is weaker and less consistent than that in Fama and French (1992). We conjecture that past book-to-market results using COMPUS-TAT data are affected by a selection bias and provide indirect evidence.  相似文献   
77.
78.
We consider an environment where two education institutions compete by selecting the proportion of their funding devoted to teaching and research and the criteria for admission for their students, and where students choose whether and where to attend university. We study the relationship between the cost incurred by students for attending a university located away from their home town and the equilibrium configuration that emerges in the game played by the universities. Symmetric equilibria, where universities choose the same admission standard, only exist when the mobility cost is high; when the mobility cost is very low, there is no pure strategy equilibrium. For intermediate values of the mobility cost, only asymmetric equilibria may exist; the final section of the paper provides an example where asymmetric equilibria do indeed exist for a plausible and robust set of parameters.  相似文献   
79.
Recent studies examining the relationship between stock returns and exchange rate changes have provided evidence that the exchange rate exposure of non-financial companies is reduced by the use of foreign exchange derivatives. Building on such research, this study investigates whether past ineffective derivative hedging contributes to explaining future derivatives use. To the extent that companies monitor the effectiveness of their currency risk management practices, past ineffective hedgers can be expected to modify their future use of foreign exchange derivatives accordingly. In our study of 94 non-financial US multinationals, we provide evidence that the change in derivatives use from 1996–1998 to 1998–2000 can be explained in part by the ineffective hedging of currency risk in 1996–1998, controlling for variables associated with theories of optimal hedging. Additional analyses confirm that such primary results are robust to firm size, the level of foreign operations, and the use of derivatives to partially hedge currency risk. Our results imply that as exchange markets and risk management practices change, the use of derivatives to manage exchange rate risk also changes. Our contribution to this field of study is that we find evidence that past ineffective hedgers tend to increase their future use of FXDs.  相似文献   
80.
On Conditional Density Estimation   总被引:1,自引:0,他引:1  
With the aim of mitigating the possible problem of negativity in the estimation of the conditional density function, we introduce a so-called re-weighted Nadaraya-Watson (RNW) estimator. The proposed RNW estimator is constructed by a slight modification of the well-known Nadaraya-Watson smoother. With a detailed asymptotic analysis, we demonstrate that the RNW smoother preserves the superior large-sample bias property of the local linear smoother of the conditional density recently proposed in the literature. As a matter of independent statistical interest, the limit distribution of the RNW estimator is also derived.  相似文献   
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