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981.
982.
983.
We experimentally investigate whether individuals can reliably detect cooperators (the nice(r) people) in an anonymous decision environment involving “connected games.” Participants can condition their choices in an asymmetric prisoners’ dilemma and a trust game on past individual (their partner’s donation share to a self-selected charity) and social (whether their partner belongs to a group with high or low average donations) information. Thus, the two measures of niceness are the individual donation share in the donation task, and the cooperativeness of one’s choice in the two games. We find that high donors achieve a higher-than-average expected payoff by cooperating predominantly with other high donors. Group affiliation proved to be irrelevant. Electronic Supplementary Material Supplementary material is available in the online version of this article at . JEL Classification C91, C72, D3  相似文献   
984.
Objective:

To define the in-hospital and 6-month post-discharge resource use, following Transcatheter Aortic Valve Implantation (TAVI) and conventional Aortic Valve Replacement (AVR) surgery within a single UK hospital.

Methods:

A local service evaluation of patients undergoing TAVI or AVR between January 2011 and May 2012 captured data until 6-months post-procedure, collected from hospital records and via a General Practitioner questionnaire. The main end-points were mortality, time in ITU/HDU, hospital length of stay (LoS), discharge destination, re-admission, and post-discharge primary/secondary care resource use. Sub-group analyses were performed for AVR patients aged ≥80 (AVR?≥?80) and with EuroSCORE of ≥10 (AVR ES?≥?10) to allow more direct comparison with ‘TAVI type’ patients.

Results:

Results are given as means (standard deviation) for TAVI (n?=?51), AVR (n?=?188), AVR?≥?80 (n?=?48), and AVR ES?≥?10 (n?=?47), respectively, unless otherwise stated. Age in years was 83.0 (8.1), 71.2 (13.1), 84.1 (2.7), 79.4 (7.1); EuroSCORE was 24.7 (11.9), 8.1 (6.4), 12.0 (6.0), and 16.5 (6.6); post-operative LoS (days) was 11.5 (11.2), 10.9 (10.8), 14.3 (16.7), and 15.2 (17.7). For discharged patients, 0%, 7%, 13%, and 9% had unplanned cardiac-related re-admissions within 30-days of discharge. Time to first readmission was 74.6 (34.0), 35.0 (34.2), 20.8 (9.7), and 22.6 (14.3) days.

Limitations:

This was a single-center retrospective evaluation, not prospectively powered to confirm differences in outcomes.

Conclusions:

Despite TAVI being performed in an older, higher risk population, LoS was similar to AVR. Most strikingly there were no cardiac-related re-admissions within 30-days for TAVI and time to first re-admission was significantly longer. This evaluation suggests that TAVI is clinically appropriate and provides economic advantages in both the hospital and post-discharge setting in this high risk group. Many patients undergoing TAVI are considered unfit for surgery and, hence, TAVI offers a treatment that delivers similar results to traditional AVR without the high risk associated with surgery.  相似文献   
985.
This study clarifies the types of motives that are important as a source of cooperation in a linear public goods experiment. Our experimental design separates contributions into those due to confusion, one-shot motives (which includes altruism, warm-glow, inequality aversion, and conditional cooperation), and multi-round motives (which includes a strategic motive under incomplete information, a failure of backward induction, and reciprocity). The experiment reveals that multi-round motives plays an important role in driving cooperative behavior. Confusion and one-shot motives play a minor role.  相似文献   
986.
Counterparty Risk and the Pricing of Defaultable Securities   总被引:19,自引:0,他引:19  
Motivated by recent financial crises in East Asia and the United States where the downfall of a small number of firms had an economy-wide impact, this paper generalizes existing reduced-form models to include default intensities dependent on the default of a counterparty. In this model, firms have correlated defaults due not only to an exposure to common risk factors, but also to firm-specific risks that are termed "counterparty risks." Numerical examples illustrate the effect of counterparty risk on the pricing of defaultable bonds and credit derivatives such as default swaps.  相似文献   
987.
We show that credit market imperfections substantially increase the government-spending multiplier when the economy enters a liquidity trap. This finding is explained by the tight association between capital goods and firms? collateral, a relationship that we highlight as the capital-accumulation channel. During a liquidity trap, a government spending expansion reduces the real interest rate, leading to a period of cheap credit. Entrepreneurs use this time to accumulate capital, which persistently improves their balance sheets and reduces their future costs of credit. A public spending expansion can thus encourage private investment, yielding consequently a large spending multiplier. This effect is further reinforced by Fisher?s debt-deflation channel.  相似文献   
988.
We estimate a dynamic factor model for the cross section of monetary and price indicators. We extract the common part of the dataset’s fluctuations and decompose it into structural shocks. We argue that one of the shocks identified has empirical properties (in terms of impulse response functions) that are fully in line with the theoretically expected relationship between money growth and inflation, confirming that the process identified has the capacity for economic interpretation. Based on this finding, we decompose recent inflationary developments in Russia into those that are associated with changes in monetary stance and other shorter-lived shocks.  相似文献   
989.
Studies dealing with the optimal choice of pollution control instruments under uncertainty have invariably taken it for granted that regulated firms face perfectly competitive markets. By introducing the product market into the stochastic framework of Weitzman (Rev Econ Stud 41:477–491, 1974), this paper shows for the case of a polluting symmetric Cournot oligopoly that Weitzman’s policy rule for choosing emission standards versus taxes with uncertain abatement costs is biased in the presence of market power. Since the oligopolists take into account their influence on the market price, their total abatement effort, including the restriction of output, is less vulnerable to miscalculations of the tax rate compared to price-taking firms. Consequently, the comparative advantage of instruments is shifted in favour of taxes. In a further step, the provided policy recommendations are generalised by abolishing the assumption that firms are symmetric.  相似文献   
990.
Technology education is a new school subject in comparison with other subjects within the Swedish compulsory school system. Research in technology education shows that technology teachers lack experience of and support for assessment in comparison with the long-term experiences that other teachers use in their subjects. This becomes especially apparent when technology teachers assess students’ knowledge in and about technological systems. This study thematically analysed the assessment views of eleven technology teachers in a Swedish context. Through the use of in-depth semi-structured qualitative interviews, their elaborated thoughts on assessing knowledge about technological systems within the technology subject (for ages 13–16) were analysed. The aim was to describe the teachers’ assessment views in terms of types of knowledge, and essential knowledge in relation to a progression from basic to advanced understanding of technological systems. The results showed three main themes that the interviewed teachers said they consider when performing their assessment of technological systems; understanding (a) a system’s structure, (b) its relations outside the system boundary and (c) its historical context and technological change. Each theme included several underlying items that the teachers said they use in a progressive manner when they assess their students’ basic, intermediate and advanced level of understanding technological systems. In conclusion, the results suggest that the analysed themes can provide a basis for further discussion about defining a progression for assessing students’ understanding about technological systems. However, the findings also need to be examined critically as the interviewed teachers’ views on required assessment levels showed an imbalance; few students were said to reach beyond the basic level, but at the same time most assessment items lay on the intermediate and advanced levels.  相似文献   
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