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991.
Treating public policies as computable dynamic general equilibrium model specification errors offers computational and conceptional advantages for comparing models with data. The set of policies calculated to rationalize observed behaviors raises the substantive economic question whether, in any particular market, actual public policies sufficiently coincide with the model's behavior-rationalizing policies, or whether the model offers correct hypotheses about the determinants of demand and supply. As illustrations, public policies are calculated to rationalize, with respect to the stochastic neoclassical growth model, capital market behavior since WWII and labor market behavior in 1929–1950. One conclusion is that capital taxation drives a wedge between consumption growth and the expected pre-tax capital return, in the direction and amount predicted by the theory, and that capital taxation is the major intertemporal distortion in the postwar capital market. Second, a good theory of the Great Depression labor market must explain why measured MRS and MPL diverged so dramatically in 1929–1933 and why the wedge persisted.  相似文献   
992.
Technology forcing is a strategy where a regulator specifies a standard that cannot be met with existing technology, or at least not at an acceptable cost. Using the 1970 U.S. Clean Air Act for controlling automobile emissions as a baseline example, we demonstrate the importance of the regulatory implementation process if regulations are to foster technological change. The 1970 legislation required steep emissions reductions for new 1975 and 1976 automobiles, which presented automakers with major technical and economic challenges. Nevertheless, the U.S. Environmental Protection Agency successfully forced the adoption of two marquee control technologies—the catalytic converter in 1975 and the three-way catalyst in 1981. We focus on three factors critical to the implementation process: agency credibility to enforce standards, competitive pressures to drive industry research and development, and uncertainty about technological development.  相似文献   
993.
This paper models sequential auctioning of two perfect substitutes by a strategic seller, who learns about demand from the first-auction price. The seller holds the second auction only when the remaining demand is strong enough to cover her opportunity cost. Bidding in anticipation of such a contingent future auction is characterized, including a sufficient condition for existence of an invertible (increasing symmetric pure-strategy) bidding equilibrium that facilitates the seller’s learning. A unique invertible bidding equilibrium exists for the Dutch auction format, but only when the second auction is sufficiently discounted by the bidders. In the equilibrium, high-valuation bidders shade their bids down as if the second auction were guaranteed. To counter such strategic bidding, the seller would value ex-ante commitment to hold the second auction less often. Three forms of such commitment are analyzed: commitment to list future auctions in advance, commitment to not hold the second auction unless the first price exceeds a publicly announced threshold, and commitment to a reserve-price in the second auction. I would like to thank Georgios Katsenos, Thomas Jeitschko, Miguel Villas-Boas, George Deltas, and an anonymous referee for thorough and insightful feedback.  相似文献   
994.
Laser scanning is a very efficient way to generate realistic, high-resolution digital models of 3-D geological outcrops. This paper discusses the methodologies involved in the creation and analysis of virtual outcrops, based on laser scanner data. The visualisation of the laser scanner data as a photorealistic 3-D object is described. Geological features picked out on the virtual outcrop (e.g. fractures, faults or bedding planes) can be extrapolated outward, into space, and inward, into the subsurface, using tension surfaces.  相似文献   
995.
Using nonparametric, production‐frontier methods, we decompose labor productivity growth into components attributable to technological change (shifts in the world production frontier), technological catch‐up (movements toward or away from the frontier), and physical and human capital accumulation (movements along the frontier). We find that (1) technological change is decidedly nonneutral, (2) productivity growth is driven primarily by physical and human capital accumulation, (3) the increased international dispersion of productivity is explained primarily by physical capital accumulation, and (4) international polarization (the shift from a unimodal to a bimodal distribution) is brought about primarily by efficiency changes (technological catch‐up).  相似文献   
996.
Scenarios are claimed to support strategic decision makers. They are especially effective in dealing with uncertainties. This paper addresses some drawbacks of the conventional scenario method, which is especially directed at handling these uncertainties, and indicates possible avenues for methodological adaptations. We take the approach, which rests in the Shell tradition, as exemplary for our discussion on the mainstream scenario methodology. This approach has some limitations when it comes to dealing with simultaneous trends and countertrends, and trends or clusters of trends that are not thought of beforehand, especially the methodological requirements of causality and consistency, which might be limiting factors in this respect. This paper indicates alternative ways for scenario construction. It discusses the use of either recombinant scenarios, context scenarios, or inconsistent scenarios and/or combinations of these scenarios. These options explicitly incorporate the notion of ‘paradoxical trend’ as the codriver of future developments into the methodology.  相似文献   
997.
Background: Inhibitor development to factor VIII (FVIII) hemophilia therapy results in increased complications and substantial economic costs. The SIPPET study, the first randomized controlled trial to compare the immunogenicity of plasma-derived FVIII (pdFVIII)/von Willebrand factor (VWF) and recombinant-DNA-derived FVIII (rFVIII), demonstrated higher inhibitor rates in previously untreated patients (PUPs) treated with rFVIII than in PUPs treated with pdFVIII/VWF.

Objective: To quantify the economic impact of treating PUPs with pdFVIII/VWF vs rFVIII.

Methods: An Excel-based clinical and economic model was developed from a US healthcare payer perspective and run over a 5-year period. The analysis utilized a cohort approach to model patient treatment and outcomes over a monthly cycle to quantify differences in costs of FVIII, bypassing agents, and hospitalizations for serious bleeds. Rates of high-titer inhibitor development were obtained from the SIPPET study. Patients developing high-titer inhibitors were treated with immune tolerance induction (ITI). Patients who developed low-titer inhibitors and those who did not develop inhibitors continued their usual FVIII treatment. Patients who were successfully treated with ITI returned to FVIII treatment, while unsuccessfully treated patients received bypassing agents. Total costs per treated patient were estimated and a one-way sensitivity analysis was conducted to quantify the impact of parameter uncertainty on the model outcomes.

Results: Total cumulative costs per patient over 5 years were $834,621 for pdFVIII/VWF patients and $1,237,163 for rFVIII patients, representing a total saving of $402,542 per patient over the 5-year period, for an average annual saving of $80,508 per patient.

Conclusions: Based on data from the SIPPET study, this analysis found that initiating FVIII treatment in severe hemophilia A PUPs with pdFVIII/VWF has the potential to offer substantial cost savings to healthcare payers, amounting to a one-third reduction in costs.  相似文献   
998.
999.
Recent research suggests that managers often make strategic decisions in novel situations by utilizing past experiences to reason by analogy. However, there is substantial evidence that decision makers often fail to identify and apply knowledge about one situation to a similarly structured situation. Two experimental studies investigated the mechanisms impacting knowledge transfer from one managerial situation (the source) to an analogous situation. The results show that exposure to variation in the source situation improves transfer performance. Variation decreases performance in the short term but improves learning and increases analogical transfer. Higher performance on and systematic search of the source situation also increase transfer performance. These results yield important implications for enhancing analogical transfer in strategic decision making and for future research on reasoning by analogy. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
1000.
This study examines the relationship between corporate social responsibility and financial performance by analyzing the intra‐industry wealth impact of additions and deletions to the Domini Social 400 index. Results from the event study analysis indicate that additions to the index generate a positive share price response for the announcement firm and a negative response by rival firms. The opposite reaction is observed for index deletions. Additionally, the share price response is more pronounced for informationally opaque industries. Our study highlights the importance of external monitoring agencies in providing meaningful information that helps resolve investor uncertainty regarding the quality of a firm's relationships with its primary stakeholders. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
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