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61.
In this paper, we present an economic analysis of CO2-enhanced oil recovery (EOR). This technique entails injection of CO2 into mature oil fields in a manner that reduces the oil's viscosity, thereby enhancing the rate of extraction. As part of this process, significant quantities of CO2 remain sequestered in the reservoir. If CO2 emissions are regulated, oil producers using EOR should therefore be able to earn revenues from sequestration as well as from oil production. We develop a theoretical framework that analyzes the dynamic co-optimization of oil extraction and CO2 sequestration, through the producer's choice of the fraction of CO2 in the injection stream at each moment. We find that the optimal fraction of CO2 is likely to decline monotonically over time, and reach zero before the optimal termination time. Numerical simulations, based on an ongoing EOR project in Wyoming, confirm this result. We also find that cumulative sequestration is less responsive to the carbon tax than to the oil price. Only at very high taxes does a tradeoff between revenues from oil output and sequestration arise.  相似文献   
62.
Trust is frequently a requirement for economic exchanges and the management of natural resources. Providing public information on past actions can promote trust through the formation of reputations. We developed an economic experiment to test whether a formal reputation mechanism could facilitate trusting relationships in the tradable grazing rights markets. Providing information to create formal public reputations for market participants did not increase the overall efficiency of the market. However, it did result in greater equality of income between partners, suggesting that participants showed more concern for their partners when they knew they would be rated. Even with public reputation information, bilateral relationships remained central to the market. Market failures in existing grazing rights markets may be better addressed by measures to increase communication between partners rather than simply relying on a formal reputation mechanism.  相似文献   
63.
We investigate the relative impact of internal Delphi process factors - including panelists' degree of confidence, expertise, majority/minority positioning - and an external factor, richness of feedback - on opinion change and subsequent accuracy of judgmental forecasts. We found that panelists who had low confidence in their judgmental forecast and/or who were in a minority were more likely to change their opinion than those who were more confident and/or in a majority. The addition of rationales, or reasons, to the numeric feedback had little impact upon panelists' final forecasts, despite the quality of panelists' rationales being significantly positively correlated with accurate forecasts and thus of potential use to aid forecast improvement over Delphi rounds. Rather, the effect of rationales was similar to that of confidence: to pull panelists towards the majority opinion regardless of its correctness. We conclude that majority opinion is the strongest influence on panelists' opinion change in both the ‘standard’ Delphi, and Delphi-with-reasons. We make some suggestions for improved variants of the Delphi-with-reasons technique that should help reduce majority influence and thereby permit reasoned arguments to exert their proper pull on opinion change, resulting in forecast accuracy improvements over Delphi rounds.  相似文献   
64.
This paper tests for differences in the cyclicality of government spending across functional categories. Evidence from 20 OECD countries suggests that procyclicality is more likely in smaller functional budgets, but capital spending is more likely to be procyclical for the larger spending categories.  相似文献   
65.
We study a contracting model with unforeseen contingencies inwhich the court is an active player. Ex ante, the contractingparties cannot include the risky unforeseen contingencies inthe contract they draw up. Ex post, the court observes whetheran unforeseen contingency occurred and decides whether to voidor uphold the contract. If the contract is voided by the court,the parties can renegotiate a new agreement ex post. There aretwo effects of a court that voids contracts. The parties' incentivesto undertake relationship-specific investment are reduced, andthe parties enjoy greater insurance against the unforeseen contingenciesthat the ex ante contract cannot account for. In this context,we fully characterize the optimal decision rule for the court.The behavior of the optimal court is determined by the trade-offbetween the need for incentives and the gains from insurancethat voiding in some circumstances offers to the agents.  相似文献   
66.
This article examines how an integrated least-cost implementation of the Kyoto Protocol in the United States would affect U.S. competitiveness and jobs. Drawing on previous work, the authors analyze integrated emission reduction strategies based on a $50/ton carbon tax (including border tax adjustments), a payroll tax cut, energy-productivity–oriented market reforms, and international flexibility mechanisms. This policy portfolios is compared to conventional approaches that omit market and fiscal reforms.
Input-output data are used to estimate the impact on export prices of goods and services produced in the United States. Similar data are used to translate changes in GDP and energy production into employment impacts in energy and nonenergy sectors. The costs of providing transitional assistance for workers in the coal industry are compared to the GDP benefits of a profitable Kyoto strategy.
The analysis shows that relative to purchasing international emission rights, productivity-raising domestic market, institutional, and fiscal reforms offer much broader advantages for tradE-exposed U.S. industries. Though allowance purchases alone increase export prices of U.S. manufactured goods and services, an integrated no-regrets strategy reduces export prices for the large majority of U.S. industries and limits the impact of climate protection policies on the few most energy-intensive basic materials industries to very small levels. Relative to the baseline, an integrated least-cost implementation of the Kyoto target increases economy-wide employment levels by several hundred thousand jobs in 2010.  相似文献   
67.
This paper attempts to explain why home ownership rates among young adults fell in the early 1990s when various indicators suggested it had become more affordable. As a potential explanation, we focus on the relatively slower growth in their incomes and argue that this could signal a fundamental change in behaviour, a change in route adopted into owner occupation, induced by structural economic change. In examining the implications for housing tenure, we use a conditional fixed effects multinomial logit model to exploit the information on the tenure choice and the timing of transitions in the British Household Panel Survey. Our results reveal that relatively slower income growth contributed significantly to this decline and that ignoring the intertemporal correlation in micro‐panels generates inconsistent results.  相似文献   
68.
We describe a method to construct an industry-by-state repeated cross-section of employment at the most disaggregated level publicly available, covering 1963–2012. Nondisclosed data are estimated with a procedure using the hierarchical information structure. To illustrate the usefulness of the procedure, the resulting estimated data are tested to determine if industrial localization of the processed food sector has changed over the last 50 years in the United States. Our findings suggest it has not changed systemically despite variation in levels of localization within industries.  相似文献   
69.
This paper experimentally compares the impact of the presence of strategic substitutes (GSS) and complements (GSC) on players’ ability to successfully play equilibrium strategies. By exploiting a simple property of the ordering on strategy spaces, our design allows us to isolate these effects by avoiding other confounding factors that are present in more complex settings, such as market games. We find that the presence of strategic complementarities significantly improves the rate of Nash play, but that this effect is driven mainly by early rounds of play. This suggests that GSS may be more difficult to learn initially, but that given sufficient time, the theoretically supported globally stable equilibrium offers a good prediction in both settings. We also show that increasing the degree of substitutability or complementarity does not significantly improve the rate of Nash play in either setting, which builds on the findings of previous studies.  相似文献   
70.
Background: Fast-tracking is an approach adopted by Mayo Clinic in Florida’s (MCF) liver transplant (LT) program, which consists of early tracheal extubation and transfer of patients to surgical ward, eliminating a stay in the intensive care unit in select patients. Since adopting this approach in 2002, MCF has successfully fast-tracked 54.3% of patients undergoing LT.

Objectives: This study evaluated the reduction in post-operative length of stay (LOS) that resulted from the fast-tracking protocol and assessed the potential cost saving in the case of nationwide implementation.

Methods: A propensity score for fast-tracking was generated based on MCF liver transplant databases during 2011–2013. Various propensity score matching algorithms were used to form control groups from the United Network of Organ Sharing Standard Analysis and Research (STAR) file that had comparable demographic characteristics and health status to the treatment group identified in MCF. Multiple regression and matching estimators were employed for evaluation of the post-surgery LOS. The algorithm generated from the analysis was also applied to the STAR data to determine the proportion of patients in the US who could potentially be candidates for fast-tracking, and the potential savings.

Results: The effect of the fast-tracking on the post-transplant LOS was estimated at approximately from 2.5 (p-value?=?0.001) to 3.2 (p-value?Conclusion: The fast-track program was found to be effective in reducing post-transplant LOS, although the reduction appeared to be less than previously reported. Nationwide implementation of fast-tracking could result in substantial cost savings without compromising the patient outcome.  相似文献   
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