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81.
The Baltimore Gas and Electric Company (BGE) undertook a dynamic pricing experiment to test customer price responsiveness to different dynamic pricing options. The pilot ran during the summers of 2008 and 2009 and was called the Smart Energy Pricing (SEP) Pilot. In 2008, it tested two types of dynamic pricing tariffs: critical peak pricing (CPP) and peak time rebate (PTR) tariffs. About a thousand customers were randomly placed on these tariffs and some of them were paired with one of two enabling technologies, a device known as the Energy Orb and a switch for cycling central air conditioners. The usage of a randomly chosen control group of customers was also monitored during the same time period. In 2009, BGE repeated the pilot program with the same customers who participated in the 2008 pilot, but this time it only tested the PTR tariff. In this paper, we estimate a constant elasticity of substitution (CES) model on the SEP pilot’s hourly consumption, pricing and weather data. We derive substitution and daily price elasticities and predictive equations for estimating the magnitude of demand response under a variety of dynamic prices. We also test for the persistence of impacts across the two summers. In addition, we report average peak demand reduction for each of the treatment cells in the SEP pilot and compare the findings with those reported from earlier pilots. These results show conclusively that it is possible to incentivize customers to reduce their peak period loads using price signals. More importantly, these reductions do not wear off when the pricing plans are implemented over two consecutive summers. Our analyses reveal that SEP participants reduced their peak usages in the range of 18 to 33% in the first summer of the SEP pilot and continued these reductions in the second summer.  相似文献   
82.
This paper takes up an argument from Ronald Rogowski about the “natural affinity” between trade and an electoral system with proportional representation. We draw on literature on the historical determinants of electoral system choice to advance the general argument that trade integration and PR are related because the adoption of PR helps to secure gains from trade. Our specific model of electoral rule changes in the age of globalization predicts that the likelihood of electoral rule change towards more proportionality increases with levels of trade integration in the world economy. The theoretical model draws on a micro model of the distributive effects of increased economic integration. Because more proportional systems are more credibly able to commit to compensate the losers of globalization processes, there will be increased demand to change the electoral system towards more proportionality under economic circumstances that increase the costs of maintaining a closed economy. In accordance with our model, our empirical tests find a positive association between (a) trade integration and the proportionality of the electoral system, (b) proportionality and social spending, and (c) global integration levels and the probability of electoral rules changes that render voting rules more proportional.  相似文献   
83.
The linking of emission trading systems (ETS) is a widely discussed policy option for future international cooperation on climate change. Benefits are expected from efficiency gains and the alleviation of concerns over competitiveness. However, from trade-theory it is known that due to general equilibrium effects and market distortions, linking may not always be beneficial for all participating countries. Following-up on this debate, we use a Ricardo-Viner type general equilibrium model to study the implications of sectoral linking on carbon emissions (‘leakage’), competitiveness, and welfare. By comparing pre- and post-linking equilibria, we show analytically how global emissions can increase if one of the ‘linked’ countries lacks an economy-wide emissions cap, although in case of a link across idiosyncratic sectors a decrease of emissions (‘anti-leakage’) is also possible. If – as a way to address concerns about competitiveness – a link between the EU ETS and a hypothetical US system is established, the partial emission coverage of the EU ETS can lead to the creation of new distortions between the non-covered domestic and international sector. Finally, we show how the welfare effect from linking can be decomposed into gains-from-trade and terms-of-trade contributions, and how the latter can make the overall effect ambiguous.  相似文献   
84.
85.
The 1990s were tumultuous times for the US Real Estate Investment Trusts (REITs) industry. Significant structural changes occurred during the decade, especially after the 1993 Revenue Reconciliation Act, which tremendously boosted the flow of funds into the system by allowing the participation of institutional investors in REITs. As a result, the industry experienced remarkable asset growth during the decade, with a large number of initial public offerings and substantial increases in market capitalization. Employing the Data Envelopment Analysis-type Malmquist index approach, this paper explores the impact of such environmental changes on productivity growth, efficiency change, and technological progress of REITs. Our results indicate that while efficiency of the REITs significantly increased, their average productivity declined and technology regressed during this decade. It appears that the typical REIT has failed to improve technically, but exerted substantial effort to catch up with the best practice ones relying mainly on aggressive growth strategies. However, our empirical results indicate that they might have overextended themselves as most began to suffer from diseconomies of scale.
Ihsan IsikEmail:
  相似文献   
86.
If some of the returns to migration accrue from returnmigration, the optimal duration of migration may be shorter thanthe feasible duration of migration. We develop a model that providesand highlights conditions under which return migration takesplace even though a reversal of the inter-country wage differentialdoes not occur. In particular, we consider the higher purchasingpower of savings (generated from work abroad) at home than abroadas a motive for return migration. Inter alia, our model producesa negative relationship between the optimal duration of migrationand the purchasing power differential and in some (but not all)cases, a negative relationship between the optimal duration ofmigration and the wage abroad. In addition, and contrary to ourprior anticipation, our utility maximization analysis suggeststhat East-West migration will tend to be temporary while inter-EuropeanCommunity (or intra-West European) migration will likely be permanent.  相似文献   
87.
A nonstationary simultaneous autoregressive model \({X^{(n)}_k=\alpha \Big(X^{(n)}_{k-1}+X^{(n)}_{k+1}\Big)+\varepsilon_k, k=1, 2, \ldots , n-1}\), is investigated, where \({X^{(n)}_0}\) and \({X^{(n)}_n}\) are given random variables. It is shown that in the unstable case α = 1/2 the least squares estimator of the autoregressive parameter converges to a functional of a standard Wiener process with a rate of convergence n 2, while in the stable situation |α| < 1/2 the estimator is biased but asymptotically normal with a rate n 1/2.  相似文献   
88.
A play-the-winner-type urn design with reduced variability   总被引:1,自引:0,他引:1  
We propose a new adaptive allocation rule, the drop-the-loser, that randomizes subjects in the course of a trial comparing treatments with dichotomous outcomes. The rule tends to assign more patients to better treatments with the same limiting proportion as the randomized play-the-winner rule. The new design has significantly less variable allocation proportion than the randomized play-the-winner rule. Decrease in variability translates into a gain in statistical power. For some values of success probabilities the drop-the-loser rule has a double advantage over conventional equal allocation in that it has better power and assigns more subjects to the better treatment. Acknowledgments. I thank Stephen Durham, the associate editor, and the referees for their helpful suggestions.  相似文献   
89.
In this paper we propose a subsampling estimator for the distribution of statistics diverging at either known or unknown rates when the underlying time series is strictly stationary and strong mixing. Based on our results we provide a detailed discussion of how to estimate extreme order statistics with dependent data and present two applications to assessing financial market risk. Our method performs well in estimating Value at Risk and provides a superior alternative to Hill's estimator in operationalizing Safety First portfolio selection.  相似文献   
90.
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