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1.
Closing the digital divide and increasing broadband adoption within households and communities continues to be a target for government and nonprofit groups. While a large number of studies have examined policies and programs aimed at improving broadband infrastructure availability, little analysis to date has focused on evaluating efforts to increase adoption. One of the most well-known programs focused on adoption is Connected Nation, which partnered with 14 states to provide local curricula aimed at raising residential connection rates. This analysis uses a generalized difference-in-difference methodology to evaluate the effectiveness of the Connected Nation program in 5 states during 2012 and 2013. The results indicate that participation in the Connected Nation program had no significant impact on broadband adoption rates. This paper represents a rigorous evaluation of one of the most well-known adoption-oriented programs and emphasizes that measurable impacts of such efforts may not accrue over the short term.  相似文献   
2.
Motivated by the implied stochastic volatility literature (Britten–Jones and Neuberger, forthcoming; Derman and Kani, 1997; Ledoit and Santa–Clara, 1998) this paper proposes a new and general method for constructing smile–consistent stochastic volatility models. The method is developed by recognising that option pricing and hedging can be accomplished via the simulation of the implied risk neutral distribution. We devise an algorithm for the simulation of the implied distribution, when the first two moments change over time. The algorithm can be implemented easily, and it is based on an economic interpretation of the concept of mixture of distributions. It can also be generalised to cases where more complicated forms for the mixture are assumed.  相似文献   
3.
Simple sufficient conditions for the existence of a unique equivalent martingale measure are provided. Furthermore, these conditions give us a handle on situations where an equivalent martingale measure cannot exist. The existence of a unique equivalent martingale measure is of relevance to problems in mathematical finance. Two examples of models for which the question of existence was unresolved are studied. By means of our results existence of a unique equivalent measure up to an explosion time is proved.  相似文献   
4.
We discuss why corruption remains high and show that corruption contributes to the Banking distress and to the rapid transmission across international stock and currency markets. Undeveloped ‘derivative securities’ markets make the risk from stress-induced volatility difficult to manage. Vinod’s (1999) closed economy model is extended to indicate the asymmetry of ‘home bias’ and the effect of corruption on the value at risk (VaR). Our theory predicts that capital flight controls will be many, foreign direct investment (FDI) will be low and cost of capital will be high in corrupt developing countries, which is supported by Asian data. We include some policy recommendations regarding financial institutions and markets.  相似文献   
5.
Modeling Conditional Yield Densities   总被引:2,自引:0,他引:2  
Given the increasing interest in agricultural risk, many have sought improved methods to characterize conditional crop-yield densities. While most have postulated the Beta as a flexible alternative to the Normal, others have chosen nonparametric methods. Unfortunately, yield data tends not to be sufficiently abundant to invalidate many reasonable parametric models. This is problematic because conclusions from economic analyses, which require estimated conditional yield densities, tend not to be invariant to the modeling assumption. We propose a semiparametric estimator that, because of its theoretical properties and our simulation results, enables one to empirically proceed with a higher degree of confidence.  相似文献   
6.
Conditional probability distributions seem to have a bad reputation when it comes to rigorous treatment of conditioning. Technical arguments are published as manipulations of Radon–Nikodym derivatives, although we all secretly perform heuristic calculations using elementary definitions of conditional probabilities. In print, measurability and averaging properties substitute for intuitive ideas about random variables behaving like constants given particular conditioning information.
One way to engage in rigorous, guilt-free manipulation of conditional distributions is to treat them as disintegrating measures—families of probability measures concentrating on the level sets of a conditioning statistic. In this paper we present a little theory and a range of examples—from EM algorithms and the Neyman factorization, through Bayes theory and marginalization paradoxes—to suggest that disintegrations have both intuitive appeal and the rigor needed for many problems in mathematical statistics.  相似文献   
7.
Estimation in the interval censoring model is considered. A class of smooth functionals is introduced, of which the mean is an example. The asymptotic information lower bound for such functionals can be represented as an inner product of two functions. In case 1, i.e. one observation time per unobservable event time, both functions can be given explicitly. We mainly consider case 2, with two observation times for each unobservable event time, in the situation that the observation times can not become arbitrarily close to each other. For case 2, one of the functions in the inner product can only be given implicitly as solution to a Fredholm integral equation. We study properties of this solution and, in a sequel to this paper, prove that the nonparametric maximum likelihood estimator of the functional asymptotically reaches the information lower bound.  相似文献   
8.
Recent work on social status led to derivation of a new continuous distribution based on the exponential. The new variate, termed the ring(2)-exponential, in turn leads to derivation of two closely related new families of continuous distributions, the mirror-exponential and the ring-exponential. Both the standard exponential and the ring(2)-exponential are special cases of both the new families. In this paper, we first focus on the ring(2)-exponential, describing its derivation and examining its properties, and next introduce the two new families, describing their derivation and initiating exploration of their properties. The mirror-exponential arises naturally in the study of status; the ring-exponential arises from the mathematical structure of the ring(2)-exponential. Both have the potential for broad application in diverse contexts across science and engineering. Within sociobehavioral contexts, the new mirror-exponential may have application to the problem of approximating the form and inequality of the wage distribution.  相似文献   
9.
We characterize the equilibrium of the all-pay auction with general convex cost of effort and sequential effort choices. We consider a set of n players who are arbitrarily partitioned into a group of players who choose their efforts ‘early’ and a group of players who choose ‘late’. Only the player with the lowest cost of effort has a positive payoff in any equilibrium. This payoff depends on his own timing vis-a-vis the timing of others. We also show that the choice of timing can be endogenized, in which case the strongest player typically chooses ‘late’, whereas all other players are indifferent with respect to their choice of timing. In the most prominent equilibrium the player with the lowest cost of effort wins the auction at zero aggregate cost. We thank Dan Kovenock and Luis C. Corchón for discussion and helpful comments. The usual caveat applies. Wolfgang Leininger likes to express his gratitude to Wissenschaftszentrum Berlin (WZB) for its generous hospitality and financial support.  相似文献   
10.
对于地震预警技术来说,根据参与监测预警的台站数量不同,可以将高速铁路地震监测预警系统分为单台站地震P波预警技术和多台站地震P波预警技术。单台站P波预警由于信息量较少以及噪声影响,在定位方面存在较大误差。多台站P波预警技术是在单台站P波预警的基础之上,综合多个单台站信息进行综合震源参数估算并发出地震预警信息的预警方式。通过应用多台站P波预警定位技术,能够在震源估算方面得到更准确的结果。  相似文献   
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