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951.
The aim of this article is to explore, through a hedonic approach, the factors that might explain the price variability for the French-managed fishery of scallop at primary fish markets. In addition to factors classically identified in the current literature like intrinsic product characteristics or markets situation, the characteristics of operators are tested. The relationships of loyalty between sellers and buyers, and market assiduity are notably considered.  相似文献   
952.
Objective: To assess the cost-effectiveness of exenatide 2?mg once-weekly (EQW) compared to dulaglutide 1.5?mg QW, liraglutide 1.2?mg and 1.8?mg once-daily (QD), and lixisenatide 20?μg QD for the treatment of adult patients with type 2 diabetes mellitus (T2DM) not adequately controlled on metformin.

Methods: The Cardiff Diabetes Model was applied to evaluate cost-effectiveness, with treatment effects sourced from a network meta-analysis. Quality-adjusted life years (QALYs) were calculated with health-state utilities applied to T2DM-related complications, weight changes, hypoglycemia, and nausea. Costs (GBP £) included drug treatment, T2DM-related complications, severe hypoglycemia, nausea, and treatment discontinuation due to adverse events. A 40-year time horizon was used.

Results: In all base-case comparisons, EQW was associated with a QALY gain per patient; 0.046 vs dulaglutide 1.5?mg; 0.102 vs liraglutide 1.2?mg; 0.043 vs liraglutide 1.8?mg; and 0.074 vs lixisenatide 20?μg. Cost per patient was lower for EQW than for liraglutide 1.8?mg (?£2,085); therefore, EQW dominated liraglutide 1.8?mg. The cost difference per patient between EQW and dulaglutide 1.5?mg, EQW and liraglutide 1.2?mg, and EQW and lixisenatide 20?μg was £27, £103, and £738, respectively. Cost per QALY gained with EQW vs dulaglutide 1.5?mg, EQW vs liraglutide 1.2?mg, and EQW vs lixisenatide 20?μg was £596, £1,004, and £10,002, respectively. In the probabilistic sensitivity analysis, the probability that EQW is cost-effective ranged from 76–99%.

Conclusion: Results suggest that exenatide 2?mg once-weekly is cost-effective over a lifetime horizon compared to dulaglutide 1.5?mg QW, liraglutide 1.2?mg QD, liraglutide 1.8?mg QD, and lixisenatide 20?μg QD for the treatment of T2DM in adults not adequately controlled on metformin alone.  相似文献   
953.
954.
We analyze optimal merger policy in R&D-intensive industries with product innovation aiming to improve the quality of products. Our results suggest that a permissive merger policy is rarely optimal in high-tech industries when the antitrust authority considers a welfare standard that balances the impact of mergers on consumers’ surplus and firms’ profits. In particular, relative to a benchmark where the effects from R&D are absent, we show that the optimal merger policy should not be substantially more permissive in the presence of those effects from R&D.  相似文献   
955.
This paper considers the assignment of tradable permits—representing property rights of an environmental good—to community members who are harmed by pollution generated by firms. These community members can in turn sell permits to polluters according to their personal preferences. For a special case with a sole household, market transactions between the household and polluters achieve an efficient pollution level. However, for a group of households, the decentralized market solution fails to yield social efficiency because of competitive consumption of the environmental goods. We design a revenue-sharing mechanism akin to unitization, under which market transactions also achieve efficient resource allocation. Importantly, in some cases, efficiency can be achieved even when regulators are ignorant of the private valuation of the environmental good.  相似文献   
956.
Using unique data from Hungary, the gap in reading and mathematics test scores between Roma and non‐Roma 8th grade students is assessed and a substantial gap between them revealed. Standardized test scores as well as the fraction of students with competences considered inadequate are examined. Regardless of measurement and subject area, the bulk of the gap is explained by social differences in income, wealth and parental education. Using reduced‐form regressions, two major mediating mechanisms are identified: first, on average the home environment of Roma children is less favourable for cognitive development; second, the educational environment of the average Roma student is different from the average non‐Roma student. Comparing students with similar home environments from the same school and class, the ethnic gap in test scores is found to be insignificant. Ethnic differences in the home environment are explained by social disparity, and ethnicity seems to play no additional role in that regard. The unequal distribution of Roma students in schools and classes is found to be explained predominantly by social difference, too, with a significant residual portion, indicating the effect of ethnic segregation.  相似文献   
957.
Smart devices such as smartphones and tablets are used extensively in public spaces for the transmission and reception of content in the form of text, photos and streaming videos. Since the bandwidth provided for wireless access is limited in public areas, it becomes an issue for users to gain access to the bandwidth they need at the right times. While an omniscient controller could assign bandwidth to each device on the basis of their needs and overall availability, imperfect information about the instantaneous state of the wifi access patterns and needs of users make for a very inefficient allocation of such bandwidth. This paper provides a solution for bandwidth allocation by creating a market among users of smart devices so that they can bid for extra bandwidth when they need it and sell it when they don’t. They do so by using a virtual currency that is conserved so that each device owner maximizes his own utility. This utility function is composed of both the benefit accrued from accessing bandwidth and the loss of the currency incurred in bidding for such bandwidth. Extensive simulations show that this market-based method outperforms an omniscient model when demand is uncertain, while minimizing bandwidth consumption.  相似文献   
958.
959.
Capital‐labour substitution and total factor productivity (TFP) estimates are essential features of many economic models. Such models typically embody a balanced growth path. This often leads researchers to estimate models imposing stringent prior choices on technical change. We demonstrate that estimation of the substitution elasticity and TFP growth can be substantially biased if technical progress is thereby mis‐specified. We obtain analytical and simulation results in the context of a model consistent with balanced and near‐balanced growth (i.e. departures from balanced growth but broadly stable factor shares). Given this evidence, a constant elasticity of substitution production function system is then estimated for the US economy. Results show that the estimated substitution elasticity tends to be significantly lower using a factor‐augmenting specification (well below one). We are also able to reject conventional neutrality forms in favour of general factor augmentation with a non‐negligible capital‐augmenting component. Our work thus provides insights into production and supply‐side estimation in balanced‐growth frameworks.  相似文献   
960.
This paper examines the wide-spread practice where data envelopment analysis (DEA) efficiency estimates are regressed on some environmental variables in a second-stage analysis. In the literature, only two statistical models have been proposed in which second-stage regressions are well-defined and meaningful. In the model considered by Simar and Wilson (J Prod Anal 13:49–78, 2007), truncated regression provides consistent estimation in the second stage, where as in the model proposed by Banker and Natarajan (Oper Res 56: 48–58, 2008a), ordinary least squares (OLS) provides consistent estimation. This paper examines, compares, and contrasts the very different assumptions underlying these two models, and makes clear that second-stage OLS estimation is consistent only under very peculiar and unusual assumptions on the data-generating process that limit its applicability. In addition, we show that in either case, bootstrap methods provide the only feasible means for inference in the second stage. We also comment on ad hoc specifications of second-stage regression equations that ignore the part of the data-generating process that yields data used to obtain the initial DEA estimates.  相似文献   
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