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361.
This paper uses the 1698 Slavonian census to illuminate features of social organization and productive activity of an eastern
European population under the New Feudalism of the 17th century. In particular we investigate the ability of community or
kinship networks to provide substitutes for missing markets in securities and production factors. It is found that kinship
networks increase the efficiency of agricultural production by facilitating the exchange of oxen. This confirms contemporary
reports that draft animals were the critical constraint to the expansion of agricultural output. We also find that kinship
networks fail to reduce the variability of output through mutual harvest insurance.
Received: 03 November 1998/Accepted: 16 June 1999 相似文献
362.
Panel count data occur in many fields and a number of approaches have been developed. However, most of these approaches are for situations where there is no terminal event and the observation process is independent of the underlying recurrent event process unconditionally or conditional on the covariates. In this paper, we discuss a more general situation where the observation process is informative and there exists a terminal event which precludes further occurrence of the recurrent events of interest. For the analysis, a semiparametric transformation model is presented for the mean function of the underlying recurrent event process among survivors. To estimate the regression parameters, an estimating equation approach is proposed in which an inverse survival probability weighting technique is used. The asymptotic distribution of the proposed estimates is provided. Simulation studies are conducted and suggest that the proposed approach works well for practical situations. An illustrative example is provided. The Canadian Journal of Statistics 41: 174–191; 2013 © 2012 Statistical Society of Canada 相似文献
363.
Gaussian process (GP) is a Bayesian nonparametric regression model, showing good performance in various applications. However, during its model-tuning procedure, the GP implementation suffers from numerous covariance-matrix inversions of expensive O(N3) operations, where N is the matrix dimension. In this article, we propose using the quasi-Newton BFGS O(N2)-operation formula to approximate/replace recursively the inverse of covariance matrix at every iteration. The implementation accuracy is guaranteed carefully by a matrix-trace criterion and by the restarts technique to generate good initial guesses. A number of numerical tests are then performed based on the sinusoidal regression example and the Wiener–Hammerstein identification example. It is shown that by using the proposed implementation, more than 80% O(N3) operations could be eliminated, and a typical speedup of 5–9 could be achieved as compared to the standard maximum-likelihood-estimation (MLE) implementation commonly used in Gaussian process regression. 相似文献
364.
Empirical Bayes methods are used in estimating the probability based on randomly right-censored samples. The estimator is shown to be asymptotically optimal. Thus, in a way, this uork is similar to the results of Hollander and Korwar (1976) who used a similar approach in estimating A in the case of non-censored data. We also give hero a shorter proof to their rate result. In addition, a. resting procedure is obtained to test the hypothesis against on the basis of censored data. It is shown that this procedure is asymptotically optimal with rate of convergence n . Tnis result is analogous to our earlier result for the uncensored case (1970) The empirical Hayes procedure has been illustrated by means of a practical example. 相似文献
365.
Francesco Caselli Wilbur John Coleman 《Journal of the European Economic Association》2013,11(Z1):161-192
When considering engaging in conflict to secure control of a resource, a group needs to predict the amount of post‐conflict leakage due to infiltration by members of losing groups. We use this insight to explain why conflict often takes place along ethnic lines, why some ethnic groups are more often in conflict than others (and some never are), and why the same groups are sometimes in conflict and sometimes at peace. In our theory ethnic markers help enforce group membership: in homogeneous societies members of the losing group can more easily pass themselves as members of the winning group, and this reduces the chances of conflict as an equilibrium outcome. We derive a number of implications of the model relating social, political, and economic indicators such as the incidence of conflict, the distance between ethnic groups, group sizes, income inequality, and expropriable resources. One of the insights is that the incidence of ethnic conflict is nonmonotonic in expropriable resources as a fraction of total resources, with a low incidence for either low or high values. We use the model’s predictions to interpret historical examples of conflict associated with skin pigmentation, body size, language, and religion. 相似文献
366.
367.
抗战期间,新四军积极吸引美术人才,在军队和根据地进行美术创作:包括木刻、油画、布画创作,宣传画、油印画、画传单,举办画展,出版画报,进行工艺、服装、舞台美术设计,建筑设计等。新四军美术创作活动,配合了抗敌斗争,服务于根据地经济建设,提高了军民的文化水平,扩大了新四军的影响。 相似文献
368.
雾霾是空气质量重要评判标准之一,对其进行准确预测能为相关政府部门及时做出正确决策提供理论支持,因此预测雾霾具有实际意义。本文针对区间灰数分布信息已知的序列,构建多个影响因素作用于多个系统行为变量的灰色MGM(1,m,N)模型。首先根据可能度函数计算得到区间灰数的新型核与灰度序列,然后对新型核与灰度序列分别建立MGM(1,m,N)模型以求得模拟值和预测值,最后通过还原得到区间灰数序列的上、下界。为进一步验证该模型的可行性,本文将该模型应用于雾霾相关数据并与基于传统核与灰度序列的MGM(1,m,N)模型进行比较,结果表明本文构建的新模型的模拟预测精度都较传统模型更好。 相似文献
369.
Jesús Fernndez‐Villaverde Jeremy Greenwood Nezih Guner 《Journal of the European Economic Association》2014,12(1):25-61
Societies socialize children about sex. This is done in the presence of peer‐group effects, which may encourage undesirable behavior. Parents want the best for their children. Still, they weigh the marginal gains from socializing their children against its costs. Churches and states may stigmatize sex, both because of a concern about the welfare of their flocks and the need to control the cost of charity associated with out‐of‐wedlock births. Modern contraceptives have profoundly affected the calculus for instilling sexual mores. As contraception improves there is less need for parents, churches, and states to inculcate sexual mores. Technology affects culture. 相似文献
370.
. The history of preindustrial Europe provides an opportunity to examine the causes and consequences of population change
at a macro level. However, serious statistical problems arise from the endogeneity of all observed variables in a Malthusian
system (fertility, mortality, population size, and real wages), and from unobserved influences such as shifts in the demand
for labor and variations in health. These problems have undermined both informal inference from the data and more complex
econometric investigations. This paper takes a new statistical approach, finding the maximum likelihood estimate of a state
space representation of the Malthusian system by repeated application of Kalman filter methods, using annual data from England,
1540 to 1870. The new estimates confirm some findings of the earlier literature and contradict others. Some variables are
estimated for the first time. Implications are discussed for the interpretation of English economic-demographic history.
Received: 3 January 2000/Accepted: 22 January 2001 相似文献