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11.
Transdisciplinarity: Context, contradictions and capacity   总被引:1,自引:0,他引:1  
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Medic (Medicago spp.) pastures are widely grown in rotation with dryland cereal crops in Mediterranean climate zones of Australia. Attempts since the 1960's to introduce this system to Mediterranean west Asia and north Africa (the native region of medic) have not lead to significant adoption; farmers in the region recognize medic, but as a weed and natural pasture plant. This first detailed economic evaluation of the rotational medic system was conducted using a whole-farm linear programming model based on the agricultural system of north-west Syria. The model represents in detail impacts of rotation on yields, labor requirements of alternative farm activities, availability of family and hired labor, subsistence income requirements, livestock feed sources and uses at different times and a choice of sheep stocking rates. Biological data for the analysis are based on a large six-year cropping and grazing experiment near Aleppo on terra-rossa soil with rainfall mainly in winter and averaging about 330 mm annually. The trial compared a dryland medic-wheat system and traditional two-year rotations of wheat with: fallow, watermelon, lentil and vetch. Results indicate that, given current prices and yields from the trial, medic is less profitable than traditional rotations. The model was used to investigate situations in which medic would be economically preferred. Selection of a medic rotation by the model was found to be particularly sensitive to the area of the farm and the price of labor. On small farms, labor availability per hectare is high, favouring the production of labor intensive crops such as lentil and watermelon. On larger farms, labor costs of these enterprises are substantial, increasing the relative profitability of medic, especially if labor prices increase. Interestingly, the relative desirability of medic is more sensitive to its impact on subsequent wheat crops than to the level of pasture production. We also found that modest increases in the prices of sheep products (especially milk) have a major impact on the economic performance of medic. These insights will allow improved focusing and targeting of future research and extension activities.  相似文献   
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This research extends the literature on nonfinancial performance measures (NFPMs) by assessing (1) the information content of a broader set of NFPMs and (2) whether NFPMs provide information not provided by financial performance measures (FPMs) from all previously identified FPM categories, rather than just earnings and book value. Specifically, exploratory and confirmatory factor analysis results presented in this paper demonstrate that nineteen NFPMs of major airlines capture seven underlying constructs not captured by eighteen common FPMs. Additionally, this research develops reliable composite measures of the identified performance measure constructs, which prior research argues are superior to individual performance measures.  相似文献   
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Summary. Combining a strategy model, an inference procedure and a new experimental design, we map sequences of observed actions in repeated games to unobserved strategies that reflect decision-makers’ plans. We demonstrate the method by studying two institutional settings with distinct theoretical predictions. We find that almost all strategies inferred are best responses to one of the inferred strategies of other players, and in one of the settings almost all of the inferred strategies, which include triggers to punish non-cooperators, are consistent with equilibrium strategies. By developing a method to infer unobserved repeated-game strategies from actions, we take a step toward making game theory a more applied tool, bridging a gap between theory and observed behavior.Received: 23 December 2002, Revised: 19 April 2005, JEL Classification Numbers: C72, C80, C90.The authors are indebted for discussions with Ray Battalio, David Cooper, Robin Dubin, John Duffy, Ellen Garbarino, Susan Helper, Margaret Meyer, John Miller, Jim Rebitzer, Mari Rege, Al Roth, and John Van Huyck. The authors also benefited from discussants at economic department seminars at Case Western Reserve, McMaster and McGill University, University of Pittsburgh, SUNY-Stony Brook, and Texas A&M, and participants at the 2002 European Winter Meeting of the Econometric Society. We are grateful for the financial support provided by the Department of Economics at the University of Pittsburgh and Case Western Reserve University.  相似文献   
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The evolution of society and economic pressure has provided the impetus for operating on a 24-hr basis in many industries. This has occurred with relatively little attention toward sleep deprivation and related problems facing shift workers and the organizations employing them. This paper first documents the move toward shift work and some sleep problems associated with it. We then describe sleep disorders that impact job performance. Next, we describe alternative schedules and give suggestions for shift work implementation. Finally, we offer some normative advice regarding the treatment of shift employees.  相似文献   
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我国企业所得税改革的国外借鉴   总被引:1,自引:0,他引:1  
20世纪90年代后期各主要发达国家为刺激经济发展进行了减税改革,其中公司所得税的改革是一个重点。我国企业所得税制存在许多亟待解决的问题,诸如内外资企业所得税制不统一、企业负担过重、税收优惠政策不合理等。借鉴国外税改经验,改革和完善我国企业所得税制。第一,合并内外资企业所得税,建立法人企业所得税制;第二,减轻企业负担,增强其竞争力;第三 ,改革和完善税收优惠政策。  相似文献   
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In the present paper, we model the policy stance of the People's Bank of China (PBC) as a latent variable, and the discrete changes in the reserve requirement ratio, policy interest rates, and the scale of open market operations are taken as signals of movement of this latent variable. We run a discrete choice regression that relates these observed indicators of policy stance to major trends of macroeconomic and financial developments, which are represented by common factors extracted from a large number of variables. The predicted value of the estimated model can then be interpreted as the implicit policy stance of the PBC. In a second step, we estimate how much of the variation in the PBC' s implicit stance can be explained by measures of its policy objectives on inflation, growth and financial stability. We find that deviations of CPI inflation from an implicit target and deviations of broad money growth from the announced targets, but not output gaps, figure significantly in the PBC's policy changes.  相似文献   
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