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We extend the entrepreneurship literature to include positive psychological capital — an individual or organization's level of psychological resources consisting of hope, optimism, resilience, and confidence — as a salient signal in crowdfunding. We draw from the costless signaling literature to argue that positive psychological capital language usage enhances crowdfunding performance. We examine 1726 crowdfunding campaigns from Kickstarter, finding that entrepreneurs conveying positive psychological capital experience superior fundraising performance. Human capital moderates this relationship while social capital does not, suggesting that costly signals may, at times, enhance the influence of costless signals. Post hoc analyses suggest findings generalize across crowdfunding types, but not to IPOs.  相似文献   
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We explore the relationship between inequality and entrepreneurial activity. Drawing on cross-sectional data from a largescale survey of the economic conditions of individuals across India, we develop a number of dimensions of inequality to explore empirically how inequality interacts with entrepreneurship, operationalized as self-employment or as employing other people. We find compelling evidence that there are thresholds to becoming self-employed, and even more so to assembling the combinations of resources and personal attributes required to become an employer. Greater inequality leaves more people unable to make the transition to self-employment, leaving casual laboring as the occupation of necessity. At the same time, inequality increases the number of employers in a society, by concentrating resources - particularly land and finance - enough for significant numbers of people to be able to cross this higher threshold. Lastly, greater differentiation into social or religious groups curtails the ability to cross either entrepreneurial threshold, presumably by limiting the extent and benefits of social networks of value for entrepreneurship.  相似文献   
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Luby变换(Luby Transform,LT)码作为信道编码应用于电力线通信(Power Line Communication,PLC),可实现电信号的可靠传输。度分布对LT码编译码性能的影响至关重要。为了得到更优的度分布,首先调整二进制指数分布(Binary Exponential Distribution,BED)中的度数比例,获得一种译码性能更优的改进的二进制指数分布(Improved BED,IBED)。然后,根据IBED在冗余度较小时译码成功率高,而冗余度增大后鲁棒孤子分布(Robust Soliton Distribution,RSD)的译码性能表现更佳的特点,通过求和归一化的方式将IBED与RSD两种度分布的优势进行有机结合,提出一种新型二进制鲁棒孤子分布(Binary RSD,BRSD)。仿真结果表明,与其他方法及传统的RSD相比,采用新度分布进行LT编码,可明显降低译码开销,并节约编译码耗时。将新型度分布应用于基于LT码的PLC系统中,能有效地抑制PLC信道中各种噪声对电信号的干扰,并提高通信效率。  相似文献   
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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   
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The focus of this paper is twofold. First, it examines the impact on work effort of changes in government purchases financed with lump‐sum taxes, in a neoclassical framework, with respect to four industrialised countries. Second, it reconsiders the expenditure–work effort relationship in a broader conceptual context that allows for distortionary taxation and a disaggregation of the income and substitution effects. Our findings are shown to cast doubt on the empirical plausibility of the prevailing (neoclassical and New Keynesian) models which seem to rely heavily on the lump‐sum tax notion, thus ignoring the substitution effects of distortionary taxation.  相似文献   
8.
Deciding on advertising appropriations is a common problem to all National Tourist Offices. The Austrian National Tourist Office now employs a decision support model allowing for inclusion of managerial judgments. In tourism, like elsewhere, application of standard optimization routines to marketing decision making is straight- forward, once the relationship linking market response to input has been modeled adequately. A tailor-made decision calculus procedure eliciting managerial judgments on the relative importance of the factors determining a receiving country's travel market share provides the weights otherwise inaccessible by objective parameter estimation. A tourism manager thus can evaluate countries as tourism generators and allocate an advertising budget accordingly.  相似文献   
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Previous research finds that large companies previously judged to be excellent growth companies have subsequently been poor investments. We examine small companies selected by Business Week on the basis of multiple criteria used in annual articles featuring highly rated growth companies. We study the investment performance over the three years before eleven annual Business Week publications and the three years after publication. We find positive excess returns in the pre‐publication period, but negative excess returns in the post‐publication period. This reversal in investment performance appears to be due to a mean‐reversion tendency in operating performance, in which the earnings and the past rates of return on capital of such companies subsequently decrease significantly.  相似文献   
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