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211.
We developed a model for estimating the fish population for various species in lakes and rivers. Our estimation focuses, in its first step, on fish species that breed outside the lake. Using the annual outside supply of fingerlings, natural survival rate and reported amounts of fish caught, we estimated fish stock. Given the estimated stock for fish bred outside the lake, we can evaluate the catch rate. Assuming equal catch rates for other species, and given the amount caught for each species, we are able to evaluate each species stock. Using the proposed technique, we evaluated various species stocks in the Sea of Galilee (Lake Kinneret) in Israel. Using our suggested technique for evaluating fish stock, we calculated the optimal effort of fishing needed for maximizing steady state profit of the fishers. 相似文献
212.
E. Feess 《Applied economics》2013,45(15):2083-2090
The literature estimating the take-out rate (price) elasticity of horse race wagering has consistently found values far above one. The persistence of these apparently inefficiently high prices can be attributed to institutional factors of the US market where federal taxes are imposed on the total amount wagered, and not on the bookmakers’ revenue. By investigating all horse races in New Zealand from August 1993 to April 2009, our article is the first one to consider price setting for wagering in an unregulated market where taxes for a monopolistic betting agency are based on revenues. In such a setting, one would expect elasticities close to one, but in all econometric specifications, we find values well below one. We identify two reasons why higher prices could nevertheless reduce profits: cross price elasticities are negative and, due to the specific features of parimutuel betting, international competitors may only be attracted when take-out rates are above a critical threshold. 相似文献
213.
This article measures irrigated agricultural outcomes under the prior appropriation doctrine by developing a model of farmers’ land allocations in response to water supply change. The modelling approach considers the institutional factors of water rights and permits the inclusive determination of water and land allocations. We utilize farm-level data of irrigated agriculture in Water District #1 in Idaho to examine the predictions from our theoretical model. The water rights priority date is consolidated at the farm level and used to differentiate farmers’ responses. We test a set of hypotheses that relate to water supply and crop revenue. Our results suggest that the water rights priority has a profound impact on agricultural outcomes, indicating strong institutional effects and weak influence of market-based approaches. Farmers respond to both long-term and seasonal water supply change and variation, and they respond to seasonal water supply forecasts in varied ways depending on their water rights portfolios, thus signalling a disproportionate distribution of potential impacts of water supply change. 相似文献
214.
The American Recovery and Reinvestment Act’s Broadband Technology Opportunities Program (BTOP) spent $4.7 billion during 2009–2013 to, inter alia, increase broadband adoption in underserved communities. We characterize the BTOP grants and examine the impact of the awards on broadband adoption. Econometric specifications controlling for award endogeneity related to observed and unobserved county-level factors find that spending is apparently associated with increased broadband adoption. Further investigation, however, reveals that the impacts of spending are nonlinear and even nonmonotonic over the range of county-level BTOP spending in the data. Controlling for trends to reduce the potential for spurious correlation between spending and outcomes removes most of the significance of the results. We conclude with three lessons for policymakers derived from the uncertain outcomes of BTOP spending found in our exploration. 相似文献
215.
The fertilizer swaps market is a potential tool to protect against fertilizer price risk. The swaps evaluated here are cash settled using The Fertilizer Index. Hedge ratios and hedging effectiveness are calculated for urea and DAP diammonium phosphate (DAP)) swaps. Urea and DAP swaps perform poorly as a hedging tool over a one-week horizon. As the hedging horizon increases, the hedging effectiveness of swaps improves. The swaps are more effective in mitigating risk across ocean freight routes than across inland routes. The limited hedging effectiveness is due to high spatial basis risk in fertilizer markets. 相似文献
216.
217.
Abstract A critical objective for many empirical studies is a thorough evaluation of both substantive importance and statistical significance. Feminist economists have critiqued neoclassical economics studies for an excessive focus on statistical machinery at the expense of substantive issues. Drawing from the ongoing debate about the rhetoric of economic inquiry and significance tests, this paper examines approaches for presenting empirical results effectively to ensure that the analysis is accurate, meaningful, and relevant for the conceptual and empirical context. To that end, it demonstrates several measurement issues that affect the interpretation of economic significance and are commonly overlooked in empirical studies. This paper provides guidelines for clearly communicating two distinct aspects of “significance” in empirical research, using prose, tables, and charts based on OLS, logit, and probit regression results. These guidelines are illustrated with samples of ineffective writing annotated to show weaknesses, followed by concrete examples and explanations of improved presentation. 相似文献
218.
Jennifer Tann Adrian E. Platts Jeremy Stein 《Technology Analysis & Strategic Management》2013,25(2):241-249
Independent Research and Technology Organizations (RTOs) provide an increasing proportion of the UK's technology services requirements. RTOs, often former state research establishments spun out into the private sector, provide technology consulting and networking services to specific sectors or for generic technologies; some are membership-based organizations while others work for contract clients. In this paper we explore the roles and services provided by RTOs, together with the measures being taken to assist small firms that, for many RTOs, form a new and challenging market. The diversity of services and approaches to SMEs are related, in part, to the different origins of RTOs. The research indicates three forms of technology services market failure that suggest a need for ongoing external support for the market's mechanism. 相似文献
219.
This paper examines the current status and prospects of heterodox approaches to economics in relation to the problem of marketing ideas to groups of potential users who see the world in very different ways. It draws lessons from the changing status of behavioural economics and highlights the marketing problems that arise between heterodox economists whose perspectives overlap only partially. Its principal message is that the best hope for heterodox economics may lie in taking a less openly combative approach than hitherto when trying to win over mainstream economists and instead using strategies of stealth based on the empirical advantages of pluralistic applied research methods. 相似文献