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971.
We study optimal portfolio choices for an agent with the aim of maximizing utility from terminal wealth within a market with liquidity costs. Under some mild conditions, we show the existence of optimal portfolios and that the marginal utility of the optimal terminal wealth serves as a change of measure to turn the marginal price process of the optimal strategy into a martingale. Finally, we illustrate our results numerically in a Cox–Ross–Rubinstein binomial model with liquidity costs and find the reservation ask prices for simple European put options.  相似文献   
972.
We consider an extension of the Markowitz mean–variance optimization framework to multiple return and risk scenarios. It is well known that asset return forecasts and risk estimates are inherently inaccurate. The method proposed provides a means for considering rival representations of the future. The optimal portfolio is computed, simultaneously with the worst case, to take account of all rival scenarios. This is a min-max strategy which is essentially equivalent to a robust pooling of the scenarios. Robustness is ensured by the noninferiority of min–max. For example, a basic worst-case optimal return is guaranteed in view of multiple return scenarios. If robustness happens to have too high a cost, guided by the min–max pooling, it is also possible to explore other pooling alternatives. A min–max algorithm is used to solve the problem and illustrate the robust character of min–max with return and risk scenarios. We study the properties of the min–max risk–return frontier and compare with the potentially suboptimal worst-case where the investment strategy and the worst case are computed separately.  相似文献   
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979.
Targeted poverty investments and economic growth in China   总被引:1,自引:0,他引:1  
In the mid-1980s, the Chinese government launched its ambitious poor area development policy, which was centered around a series of grant, credit, and Food-for-Work programs. Ironically, for the remainder of the 1980s rural poverty remained at about 90 to 100 million, or approximately 10% of the rural population. The lack of progress cannot necessarily be blamed on ineffective poor area policies, since much of the agricultural economy was mired in a deep recession between the mid-1980s and the early 1990s. By the mid-1990s substantial additional poverty reduction had been achieved. Even in the late-1980s, farmers in many poor counties did better than the national average in terms of income growth. After accounting for the effects of macroeconomic elements, what factors can help explain the differences in performance among poor regions and between poor areas and rich ones? Can part of these differences be accounted for by poor area policies, in general, or by the way local and regional officials allocate their poor area investment funds, in particular?The overall objective of this paper is to analyze the effectiveness of Chinese poor area policy. Specifically, the paper seeks to meet three objectives. First, we want to understand the evolution of poor area policy since the mid-1980s, trying to deduce the true goals of central and regional poor area officials, as well as how these policies have been implemented in the provinces. Next, we want to understand the magnitude and scope of investment into poor areas, and examine if changes in these policies have affected the uses of the investment funds. Finally, we want to determine the effectiveness of the investment of poor area funds, analyzing which types of investments have generated growth, and which ones have not.  相似文献   
980.
This paper extends the bargaining and matching literature, such as Rubinstein and Wolinsky (1985), by considering a new matching process. We assume that a central information agency exists, such as real estate agencies in the housing market and employment agencies (or newspapers) in the labour market, which puts traders into direct contact with each other. With heterogeneity of trader preferences, equilibrium trade is characterized by existing traders on each side of the market trying to match with the flow of new traders on the other side (since existing traders have already sampled and rejected each other). Two procedures of trade co-exist, namely a strategic bilateral bargaining process and a competitive bidding process, depending on the number of potential matches a new trader obtains. We characterize the unique symmetric Markov perfect equilibrium to this stochastic trading game.  相似文献   
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