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111.
In this paper, we analyze a specific class of principal-agent models which seems to be sufficiently general to cover applications in environmental economics with upstream-downstream problems as an example. In our basic model, the observation outcome is ann-dimensional random vectorx and only the first and second moments ofx are common knowledge. We study the effects of random sampling in the presence of costly signals. For this purpose, we assume that the principal and the agent use a simple statistical procedure, i.e. their contract will be based on the mean of a random sample with sampling costs dependent on the sample size. It is shown that there exists an optimal sample size. We investigate the relationship between the optimal sample size, the marginal sampling costs, and the agent's risk aversion. 相似文献
112.
Taka-aki Shiraishi 《Annals of the Institute of Statistical Mathematics》1991,43(4):715-734
Multiresponse experiments in two-way layouts with interactions, having equal number of observations per cell, are considered. Robust procedures based on aligned ranks for statistical inference of interactions, main effects and an overall mean response in the models are proposed. Large sample properties of the proposed tests, estimators and confidence regions as the cell size tends to infinity are investigated. For the univariate case, it is found that the asymptotic relative efficiencies (ARE's) of the proposed procedures relative to classical procedures agree with the ARE-results of the two-sample rank test relative to the t-test. In addition, robustness due to Huber (1981, Robust Statistics, Wiley, New York) can be drawn. 相似文献
113.
In a variety of statistical problems one needs to solve an equation in order to get an estimator. We consider the large sample properties of such estimators generated from samples that are not necessarily identically distributed. Very general assumptions that lead to the existence, strong consistency, and asymptotic normality of the estimators are given. A number of results that are useful in verifying the general assumptions are given and an example illustrates their use. General applications to maximum likelihood, iteratively reweighted least squares, and robust estimation are discussed briefly. 相似文献
114.
Zenon J. Jablonski 《Proceedings of the American Mathematical Society》2007,135(9):2811-2819
An operator multivariate moment problem with contractive solutions having regular unitary dilation is characterized in terms of the initial data. This extends a recent result of Sebestyén and Popovici, but the ideas of our proof differ from those used by them. The connection between the operator multivariate moment problem and harmonizable multivariate discrete processes is mentioned.
115.
For a sequence of partial sums ofd-dimensional independent identically distributed random vectors a corresponding multivariate renewal process is defined componentwise. Via strong invariance together with an extreme value limit theorem for Rayleigh processes, a number of weak asymptotic results are established for thed-dimensional renewal process. Similar theorems for the estimated version of this process are also derived. These results are suggested to serve as simultaneous asymptotic testing devices for detecting changes in the multivariate setting. 相似文献
116.
Alberto Ferrer Daniel Aguado Santiago Vidal‐Puig José Manuel Prats Manuel Zarzo 《商业与工业应用随机模型》2008,24(6):551-567
Modern industrial processes are characterized by acquiring massive amounts of highly collinear data. In this context, partial least‐squares (PLS) regression, if wisely used, can become a strategic tool for process improvement and optimization. In this paper we illustrate the versatility of this technique through several real case studies that basically differ in the structure of the X matrix (process variables) and Y matrix (response parameters). By using the PLS approach, the results show that it is possible to build predictive models (soft sensors) for monitoring the performance of a wastewater treatment plant, to help in the diagnosis of a complex batch polymerization process, to develop an automatic classifier based on image data, or to assist in the empirical model building of a continuous polymerization process. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
117.
M.E Bock 《Journal of multivariate analysis》1985,17(2):127-147
Let X be a p-dimensional random vector with density f(6X?θ6) where θ is an unknown location vector. For p ≥ 3, conditions on f are given for which there exist minimax estimators θ?(X) satisfying 6Xt6 · 6θ?(X) ? X6 ≤ C, where C is a known constant depending on f. (The positive part estimator is among them.) The loss function is a nondecreasing concave function of 6θ?? θ62. If θ is assumed likely to lie in a ball in p, then minimax estimators are given which shrink from the observation X outside the ball in the direction of P(X) the closest point on the surface of the ball. The amount of shrinkage depends on the distance of X from the ball. 相似文献
118.
Ludger Rüschendorf 《Annals of the Institute of Statistical Mathematics》1985,37(1):225-233
Summary We make some remarks on the problem how to construct probability measures with given marginals. Questions of this kind arise
if one wants to build a stochastic model in a situation where one has some idea of the kind of dependence and knows exactly
certain marginal distributions. 相似文献
119.
Takafumi Isogai 《Annals of the Institute of Statistical Mathematics》1985,37(1):289-301
Summary Some extension of Haldane's multivariate median is carried out by minimization principle of a specified distance function.
Then, making use of the median, three types of measures of multivariate skewness are introduced and their asymptotic null
distributions are obtained. 相似文献
120.
Irwin Guttman Ulrich Menzefricke 《Annals of the Institute of Statistical Mathematics》1982,34(1):319-326
Summary We consider a sequence of independent random variables whose densities depend on a parameter which is subject to a change
at an unknown time point. A Bayesian decision-theoretic approach is used to obtain an optimal choice of changepoint. The exponential
and multivariate normal models are analyzed, and some numerical examples are given. 相似文献