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951.
952.
Kenya is a globally recognized maize “success story.” As the overall percentage of maize farmers growing hybrids tops 80% and the seed industry matures, the slow pace of hybrid replacement on farms, and the continued dominance of the seed industry by Kenya Seed Company, may dampen productivity. Our econometric analysis identifies the factors that explain farmer demand for hybrid seed, and the age of hybrids they grow, considering hybrid seed ownership. Male‐headed households with more education, more assets, and more land plant more hybrid seed. Scale of seed demand per farm is differentiated by agroecology. We find a strong farmer response to the seed‐to‐grain price ratio, which we interpret as evidence of a commercial orientation even on household farms. However, despite the dramatic increase in the number of hybrids sold and the breadth of seed suppliers as seed markets liberalize, an older hybrid still dominates national demand.  相似文献   
953.
Solidarity has long been considered essential to labour, but many fear that it has declined. There has been relatively little scholarly investigation of it because of both theoretical and empirical difficulties. This article argues that solidarity has not declined but has changed in form, which has an impact on what kinds of mobilization are effective. We first develop a theory of solidarity general enough to compare different forms. We then trace the evolution of solidarity through craft and industrial versions, to the emergence of collaborative solidarity from the increasingly fluid ‘friending’ relations of recent decades. Finally, we examine the question of whether these new solidarities can be mobilized into effective collective action, and suggest mechanisms, rather different from traditional union mobilizations, that have shown some power in drawing on friending relations: the development of member platforms, the use of purposive campaigns and the co‐ordination of ‘swarming’ actions. In the best cases, these can create collective actions that make a virtue of diversity, openness and participative engagement, by co‐ordinating groups with different foci and skills.  相似文献   
954.
955.
We develop a partial equilibrium, perfectly competitive framework of a (potentially) vertically integrated industry. There are three types of firms: upstream firms that use primary factors to produce an intermediate good; downstream firms that use primary factors and intermediate goods to produce a final good; and vertically integrated firms that do both. We establish conditions under which vertically integrated firms exist and outsource (part of) the production of the intermediate input. We study the changes in industry configurations resulting from changes in costs and demand.  相似文献   
956.
957.
958.
We examine the implications of changing competitive dynamics in global information and communications technology (ICT) markets for government demand-steering policies whose goal is local rents. Both computing and telephony are undergoing changes in global industry structure and changes in the nature of competition. The convergence of computing and telephony and the rapid technological change (and accompanying technological uncertainty) driving this convergence reinforce trends toward vertical competition. The emergence of global ICT markets lowers entry barriers, likely encouraging government-supported local entrants into global ICT markets. There are, however, strongly offsetting disadvantages. The underlying economics of ICT markets under vertical competition will work to reinforce the dominant position of U.S.-based incumbents in many segments. The prospects for exports, command of rent-related standards, and large rents from exports are not very bright. We expect to see far more demand-steering attempts than successes. J. Japan. Int. Econ., December 1999, 13(4), pp. 336–371. Landau Economics Building, Department of Economics-6072, Stanford, California 94305-6072; and International Computer Services Research, Stanford Computer Industry Project, Landau Economics Building, SIEPR 144, Stanford, California 94305-6016. Copyright 1999 Academic Press.Journal of Economic Literature Classification Numbers: L5, F110.  相似文献   
959.
This paper studies announcement returns of Western European acquisitions of private and public targets. It uses a contingent claims perspective to offer a new explanation for the difference in abnormal returns between acquirers of private and public targets. In this context, an acquisition is analogous to buying a call option and the value of the acquirer increases with uncertainty about its growth prospects (options). We test this idea by studying the relation between announcement returns and acquirer's characteristics that proxy for the existence of growth options. Consistent with the contingent claims hypothesis, the private acquisition gains are associated with the combined effects of growth options (having higher runup before the acquisition announcement) with low level of leverage (near-all equity capital) and with uncertainty (measured by age and analyst coverage of acquirers).  相似文献   
960.
The authors examine class size, teaching methods, and the one-semester/two-semester organization of the first course in economics, where colleges and universities are classified into five broad categories, from liberal arts colleges to research institutions. Student satisfaction with respect to their institution is also reported.  相似文献   
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