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961.
This paper examines a scheme of economic incentives for environmental protection, in which spatially differentiated pollution taxes are in use in compensating the pollution abatement costs. A simple mathematical model is described which determines an incentive system that encourages polluters to reduce the discharges to an acceptable level of ambient quality standards in a cost-effective manner. It is shown that the vector of pollution charges has to be proportional to the marginal abatement cost vector, but is smaller than the latter in magnitude. It is demonstrated that a necessary incentive effect may be achieved even if the total pollution charge is much lower (about three times) than the total abatement costs. It is also estimated how this charge incentive system reconciles conflicting criteria of cost-effectiveness and of equity. These conclusions are verified by numerical experiments with real data.  相似文献   
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Ohne Zusammenfassung  相似文献   
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We empirically investigate the interactions among hedging, financing, and investment decisions. We argue that the way in which hedging affects a firm's financing and investing decisions differs for firms with different growth opportunities. We find that high growth firms increase their investment, but not leverage, by hedging. However, we also find that firms with few investment opportunities use derivatives to increase their leverage.  相似文献   
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This paper studies the use of patent statistics in identifying four aspects of technological structure, namely, the potential knowledge pool, cumulativeness, inter-firm homogeneity in technology levels, and the scope of innovations. The firms are sampled from the chemical (CHEM), the computer (COM) and the electrical and electronic (EE) industries worldwide. Using the proxies defined, we find that (i) the contributions of intra-industry spillover are low, at 12%, 10%, and 9% for the three industries respectively; (ii) they can internalize 15%, 19% and 13% of their previous research efforts respectively; and (iii) a positive relationship between knowledge spillover and technology overlap, and between scope of innovation and number of patents being cited in future.  相似文献   
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Robust institutional change is difficult to achieve. However, it is more difficult for some countries than others. We use data on 69 countries between 1870 and 2000 to show that political instability does not always affect growth outcomes. We then develop a simple model to explain this fact in which the likelihood that “good” institutions are abandoned during periods of political uncertainty depends on the opportunity cost of doing so. We operationalize our model by using contract intensive money as a proxy for this initial investment in growth‐enhancing institutions. Cross‐sectional and panel growth regressions support the model's predictions.  相似文献   
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D. A. Peel 《Applied economics》2018,50(22):2431-2438
Punters may engage in betting on both a selection in an event to finish first or in one of the number of places, e.g. second, third or fourth. When the amounts staked with bookmakers at fixed odds on the win and place are equal, it is called an each-way bet. Each-way bets are apparently popular with punters but inconsistent with prominent models of wagering which assume gamblers are everywhere risk-seeking. In this note, we derive the conditions for win and place bets to be optimal in these three models of risky choice. The mathematical conditions for the each-way wager to be optimal, as opposed to a win and place wager with different stakes, are complicated and appear likely to occur rarely in practice. However, bettors obviously see the attraction in giving themselves two ways to bet on the one horse or two ways to win and betting each way. We suggest part of the ‘each-way’ betting attraction is that they are quick and easy to compute – a heuristic – to solve an otherwise complex betting strategy.  相似文献   
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