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991.
992.
Natural and man-made disasters imply a great deal of uncertainty in terms of potential damage, though it is certain that there would be a huge spike in the demand for relief supplies causing shortages and/or delays in providing aid. Ruptures in the infrastructure (roads, utility, and communication lines) cause additional delays due to repairs. Therefore, the relief providers need to work in collaboration with retailers, and infrastructure service providers for improving responsiveness. The relief providers (government and non government) rely on acquiring and delivering supplies in real time because such actions accompany little risk of resource underutilization, though the cost of real time acquisitions can be high. In contrast, a proactive response, while minimizing acquisition cost, can be very ineffective if demand surges are high. We study a hybrid of reactive and proactive approaches, where the reactive response is contingent upon the disaster intensity exceeding a certain threshold. We show how the threshold value may impact capacity acquisitions and prices and establish the optimality of contingent response. Further, we establish how an infrastructure contract may help reducing the social cost of disaster.  相似文献   
993.
When the interest rate on a currency that is pegged to a basket differs from the interest rate on the basket (as a weighted average), it is possible to make profit from interest arbitrage by going short on the basket and long on the pegged currency, or vice versa. This proposition is illustrated by using data on the Kuwaiti dinar and its basket currencies over the period 1998–2002 when the currency was pegged to a basket. Monte Carlo simulations show that the probability of making arbitrage profit from any single operation is about 95%.  相似文献   
994.
In this paper, we discuss the substitution effects between mobile games and console games. We estimate such effects by a fixed-effect regression with instrumental variables using panel data of about 100,000 observations. The results showed that the substitution effects of playing smart devices on 3DS, Wii, and PSP were recognizable, but did not have significant effects on PS3, and the substitution effects on PSP were very small. Therefore, mobile games had a substitution effect on casual console games, or on console games in which the play situation resembled mobile games. In addition, the substitution effects were at most about 0.1. The substitution effects were small. Our results indicate that mobile games represent the pioneers in the new market of gaming at least during our observation period. But new games and traditional games will coexist for a while.  相似文献   
995.
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998.
Ensemble methods can be used to construct a forecast distribution from a collection of point forecasts. They are used extensively in meteorology, but have received little direct attention in economics. In a real-time analysis of the ECB’s Survey of Professional Forecasters, we compare ensemble methods to histogram-based forecast distributions of GDP growth and inflation in the Euro Area. We find that ensembles perform very similarly to histograms, while being simpler to handle in practice. Given the wide availability of surveys that collect point forecasts but not histograms, these results suggest that ensembles deserve further investigation in economics.  相似文献   
999.
1000.
This study explores gender differences in positive perceptions, anxiety, and depression among mothers and fathers of children with intellectual disabilities (IDs). We examined the relationship between these variables and certain characteristics of both the child (age and severity of disability) and the parents (age, educational level, and employment status). A sample of 60 mother/father couples who had children with IDs completed the Positive Contributions Scale to measure their positive perceptions, and the Hospital Anxiety and Depression Scale to assess their level of anxiety and depression. Bivariate analyses were used to determine differences between fathers and mothers as regards their positive perceptions and levels of anxiety and depression. A logistic regression model was then applied to identify which of the variables might be significant predictors of the gender differences observed among parents. Both mothers and fathers had positive perceptions of their children with IDs that co-existed with symptoms of anxiety and depression, with scores being higher among mothers. The predictive analysis of gender showed that individual variables (such as the employment status of both parents) may explain these differences.  相似文献   
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