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951.
Allocating resources to competing large‐scale infrastructure projects involves multiple objectives. Traditional decision‐aiding methodologies focus on the trade‐offs among performance and resource objectives. Existing methodologies may fail to account for unknown and emergent risks that are typical of large‐scale infrastructure investment allocation problems. In modern portfolio theory, it is well known that a diversified portfolio can be very effective to reduce non‐systematic risks. The approach of diversification is equally important in choosing robust portfolios of infrastructure projects that may be subject to emergent and unknown risks. In this paper, we demonstrate a methodology to analyze and compare the diversification of portfolios of large‐scale infrastructure projects. We classify and explore several metrics of diversification and integrate them with risk and other performance objectives in a multiobjective approach. We test the new metrics and the methodology in a case study of hundreds of millions of dollars of infrastructure investments. The results suggest that the solutions that consider diversification are more robust to emergent risks, thus, identifying an opportunity to incorporate diversification‐based optimization methodologies to support a variety of problems involving large‐scale infrastructure investments.  相似文献   
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The Mississippi Bubble, South Sea Bubble and the Dutch Windhandel of 1720 together represent the world's first global financial bubble. We hand-collect cross-sectional price data and investor account data from 1720 to test theories about market bubbles. Our tests suggest that innovation was a key driver of bubble expectations. We present evidence against the currently prevailing debt-for-equity conversion hypothesis and relate stock returns to innovations in Atlantic trade and insurance. We find evidence consistent with the innovation-driven bubble dynamics documented by Pastor and Veronesi (2009) for new economy stocks. Our evidence seems inconsistent with clientele-based theories that emphasize bubble-riding and short-sales restrictions.  相似文献   
955.
Abstract

1. It is well known that the frequency distribution resulting from repetitions of an observation may be represented by a collection of rational, integral and symmetrical functions of the observations, the most frequently employed functions of this kind being the moments and the semi-invariants. Following the notation of Thiele 1 we shall denote the rth moment about the origin by sr , and the rth semi-invariant by µr.  相似文献   
956.
We exploit a unique sample to analyze how homophily (affinity for similar others) and social ties affect career outcomes in banking. We test if these factors increase the probability that the appointee to an executive board is an outsider without previous employment at the bank compared to being an insider. Homophily based on age and gender increase the chances of the outsider appointments. Similar educational backgrounds, in contrast, reduce the chance that the appointee is an outsider. Greater social ties also increase the probability of an outside appointment. Results from a duration model show that larger age differences shorten tenure significantly, whereas gender similarities barely affect tenure. Differences in educational backgrounds affect tenure differently across the banking sectors. Maintaining more contacts to the executive board reduces tenure. We also find weak evidence that social ties are associated with reduced profitability, consistent with cronyism in banking.  相似文献   
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We assess the importance of supply‐side credit market frictions by studying the impact of bank recapitalization on firm growth in 50 countries during the recent crisis. Our identification strategy exploits the crisis as a shock to credit supply and combines an exogenous measure of firms’ dependence on external financing with policy interventions aimed at restoring bank capital. We find that the growth of financially dependent firms is disproportionately positively affected by bank recapitalization. This effect is quantitatively important and robust to controlling for other policies. These results provide new evidence of the influence of credit market frictions on economic activity.  相似文献   
959.
The parameters of the short-run cost function are estimated for three vessel types taking part in the Norwegian pelagic fisheries: purse seine vessels, trawlers, and coastal vessels. The generalized translog functional form is used. Estimates of returns to scale are calculated and the results indicate that there are substantial economies of scale in all vessel classes. It is further investigated whether excess capacity varies with vessel size and age. The analysis suggests increased quotas per vessel to avoid rent dissipation. With the total allowable catch given, the number of participating vessels must be reduced.  相似文献   
960.
We developed a model for estimating the fish population for various species in lakes and rivers. Our estimation focuses, in its first step, on fish species that breed outside the lake. Using the annual outside supply of fingerlings, natural survival rate and reported amounts of fish caught, we estimated fish stock. Given the estimated stock for fish bred outside the lake, we can evaluate the catch rate. Assuming equal catch rates for other species, and given the amount caught for each species, we are able to evaluate each species stock. Using the proposed technique, we evaluated various species stocks in the Sea of Galilee (Lake Kinneret) in Israel. Using our suggested technique for evaluating fish stock, we calculated the optimal effort of fishing needed for maximizing steady state profit of the fishers.  相似文献   
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