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Competition was introduced into the electric utility industry with the passage of the Public Utilities Regulatory Policy Act (PURPA) of 1978. Increasing interest has appeared in structuring the PURPA purchase market into an auction system. This paper addresses the design issues associated with setting up such markets and introduces a simulation model to study them. The simulation analysis is guided by theoretical issues such as the alleged inefficiency of first-price auctions. We find that efficiency concerns raised about first-price auctions turn out to be less important than simple theoretical concerns would suggest.  相似文献   
134.
Indicators of market power can be ambiguous because cost economies associated with scale and not market imperfections may influence results. This article illustrates that without direct measures of concentration, estimates of costs, scale economies and profitability can be used to identify market power in banking. Secondly, via this method, econometric estimates provide meaningful evidence of market power in the South African banking sector over the study sample period (1979–1998). A reasonable conclusion is that while industrial structure is important, careful consideration needs to be given to cost economies and profitability when assessing market power. In addition, there is a need to consider appropriate policy to reduce market power in banking in South Africa.  相似文献   
135.
Individual bid functions display sensitivity to the strategic considerations inherent in first-price auctions. However, several formal models, including heterogeneous Nash equilibrium bidding models with constant relative risk aversion, perform quite poorly.  相似文献   
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Researching Preferences,Valuation and Hypothetical Bias   总被引:1,自引:0,他引:1  
A number of recent papers in environmental economics have focused on the process of researching preferences – agents are uncertain about preferences but with effort may narrow their uncertainty. This issue has arisen in formulating bids in contingent valuation (CV) as well as the debate over the divergence between WTP and WTA. In the context of CV, it has been suggested that the hypothetical nature of the preference elicitation process biases responses. This paper provides both a theoretical model and experimental evidence to contribute to this debate. The model is a model of competitive bidding for a private good with two components that are particularly relevant to the debate. The first component is that bidders are unsure of their own value for the private good but may purchase information about their own value (researching preferences). The second component is that there is a probability that the auction is hypothetical – that the winning bidder will not get the private good and will not pay the winning bid. The experiment tests this theoretical model of bidding equilibrium and analyzes the effects of variations in the parameters (hypotheticalness, information costs and number of agents) on the endogenous variables (such as the proportion of bidders who become informed and the winning bid). Experimental results suggest that an increase in the hypotheticalness of an auction tends to decrease the likelihood that bidders pay for information on their valuation with an ambiguous effect on the winning bid.   相似文献   
138.
Emission of CO2, SO2 and NOx are all closely linked to the burning of fossil fuels. Here we report on simulations done by linking a Sectoral European Energy Model (SEEM), covering energy demand in nine Western European countries, with the emission-transport-deposition model RAINS developed by IIASA. The study analyses emissions of CO2, SO2 and NOx, deposition of sulphur and nitrogen and the extent of areas where the critical load for sulphur is exceeded in year 2000 under four different energy scenarios. Two different sets of future behavioural patterns for the thermal electric power production sector are considered. In one regime, called the plan-efficient regime, the sector is assumed to follow official plans with regard to investment in new capacity. In the other regime, called the cost-efficient regime, the thermal power sector is assumed to behave in a cost minimizing manner. The effects of the proposed EC carbon/energy tax are studied under both regimes, giving rise to altogether four scenarios.In both regimes the effect of the EC tax is to reduce emissions by between 6 and 10 per cent in year 2000 relative to the scenarios without the tax. A change of regime, from the regulated, plan-efficient regime to the market-based, cost-efficient regime, will, by itself, reduce emissions of CO2 and NOx by approximately 3 per cent, while SO2 emissions are reduced by 13 per cent. The EC tax will reduce sulphur deposition by more than 5 per cent in the nine model countries under the plan-efficient regime. A change of regime further reduces the total deposition by 9 per cent. The area where depositions exceed the critical load is reduced by approximately 6 per cent in year 2000 by the tax in both regimes. Changing from the plan-efficient to the cost-efficient regime has a similar impact.Although the emission reductions due to the EC tax may seem modest, they are shown to have a sizeable effect on the technological abatement costs of reaching targets like those prescribed in the Sofia protocol on the stabilisation of NOx emissions, and the Helsinki protocol on SO2 emission reductions. This is part of what can be considered to be secondary benefits of the EC carbon/energy tax.  相似文献   
139.
A bstract .   State-sponsored lotteries are a lucrative source of revenue. Despite their low payout rates, lotteries are extremely popular, particularly among low-income citizens. State officials laud the benefits of lottery proceeds and promote the fun and excitement of participation. This entertainment value is one explanation for lottery demand by the poor: individuals with lower incomes substitute lottery play for other entertainment. Alternatively, low-income consumers may view lotteries as a convenient and otherwise rare opportunity for radically improving their standard of living. Bad times may cause desperation, and the desperate may turn to lotteries in an effort to escape hardship. This study tests these competing explanations. We examine lottery sales data from 39 states over 10 years and find a strong and positive relationship between sales and poverty rates. In contrast, we find no relationship between movie ticket sales, another inexpensive form of entertainment, and poverty rates.  相似文献   
140.
Zusammenfassung Es wird gezeigt, daß sich das vonNeyman undTschuprow für ein einziges Merkmal gelöste Problem der optimalen Aufteilung des Stichprobenumfangs auf vorgegebene Schichten auf ein nichtlineares Programm mit linearen Restriktionen und nichtlinearer Zielfunktion zurückführen läßt. Auf Grund der Konvexitätseigenschaft der Zielfunktion ergibt sich, daß das Minimum der Zielfunktion (Minimum der Streuung des Stichprobenmittels ) stets eindeutig ist. Der beiNeyman undTschuprow mögliche Fall, daß sich in derh-ten Schicht ein Stichprobenumfang ergibt, der größer als der Umfang in der Gesamtheit ist, kann hier nicht auftreten.Durch Einführung einer verallgemeinerten Streuung wird das Problem der optimalen Aufteilung bei vorgegebener Schichtung imk-dimensionalen Merkmalsraum aufk Merkmale verallgemeinert. Es wird gezeigt, daß diese verallgemeinerte Streuung (=Zielfunktion eines nichtlinearen Programms) im allgemeinen nicht über dem ganzen konvexen Bereich der zulässigen Lösungen konvex (von unten) ist. Ein Teilbereich des zulässigen Bereichs, über dem die Zielfunktion konvex ist, wird angegeben. Schließlich werden hierzu vergleichende Ergebnisse gebracht.  相似文献   
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