共查询到10条相似文献,搜索用时 46 毫秒
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The problem of estimating the mean average total cost of each output for multiproduct firms in an industry is addressed. The identity that defines total cost for each firm as the product of output levels multiplied by their respective average total costs is viewed as a random-coefficients model. A random coefficients regression estimator is used to estimate mean average total output costs. Solutions to problems arising with this method in empirical studies are discussed. An application of the approach to data from cash grain farms in Illinois shows that the method gives reliable estimates for per-unit output production costs with considerably fewer data requirements than current methods of cost estimation. 相似文献
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《统计与信息论坛》2018,(8):19-30
两阶段估计方法是解决计量模型变量内生性问题的重要方法,而现代社会科学领域的研究文献在选择两阶段估计方法时存在较多误区,缺乏比较系统的研究。基于多项分布内生回归元的计数模型,采用蒙特卡洛模拟比较2SLS、2SPS、2SRI三种两阶段估计方法的优劣,并从检验水平和功效角度评价Wald、LR、LM三种内生性检验方法的有效性,结果发现:当忽略模型非线性、内生性或错误设定计数数据分布时,2SLS和2SPS均会存在较大的估计偏差,但2SRI估计量具有良好的有限样本特征;基于2SRI的三种内生性检验方法,在计数数据分布设定正确时都有合理的实际检验水平和功效,但在忽略计数数据过度分散特征时,Wald和LR检验统计量会发生严重的水平扭曲,而LM检验则更有效。 相似文献
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Estimation in Degradation Models with Explanatory Variables 总被引:1,自引:0,他引:1
Influence of covariates on degradationis modelled. Models which include dependence of the intensityof the process of traumatic events on the degradation level arealso discussed. Estimation of reliability and degradation characteristicsfrom data with covariates is considered in dynamic environments. 相似文献
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The average availability of a repairable system is the expected proportion of time that the system is operating in the interval [0, t]. The present article discusses the nonparametric estimation of the average availability when (i) the data on ‘n’ complete cycles of system operation are available, (ii) the data are subject to right censorship, and (iii) the process is observed upto a specified time ‘T’. In each case, a nonparametric confidence interval for the average availability is also constructed. Simulations are conducted to assess the performance of the estimators. 相似文献
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ABSTRACTWe study estimation and inference when there are multiple values (“matches”) for the explanatory variables and only one of the matches is the correct one. This problem arises often when two datasets are linked together on the basis of information that does not uniquely identify regressor values. We offer a set of two intuitive conditions that ensure consistent inference using the average of the possible matches in a linear framework. The first condition is the exogeneity of the false match with respect to the regression error. The second condition is a notion of exchangeability between the true and false matches. Conditioning on the observed data, the probability that each match is correct is completely unrestricted. We perform a Monte Carlo study to investigate the estimator’s finite-sample performance relative to others proposed in the literature. Finally, we provide an empirical example revisiting a main area of application: the measurement of intergenerational elasticities in income. Supplementary materials for this article are available online. 相似文献
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In this article, we define the geometric mean of a nonnegative random variable in different cases and study the asymptotic unbiasedness of the sample geometric mean. 相似文献
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You-Gan Wang 《Australian & New Zealand Journal of Statistics》1998,40(3):299-304
The von Bertalanffy growth model is extended to incorporate explanatory variables. The generalized model includes the switched growth model and the seasonal growth model as special cases, and can also be used to assess the tagging effect on growth. Distribution-free and consistent estimating functions are constructed for estimation of growth parameters from tag-recapture data in which age at release is unknown. This generalizes the work of James (1991, Biometrics 47 1519–1530) who considered the classical model and allowed for individual variability in growth. A real dataset from barramundi ( Lates calcarifer ) is analysed to estimate the growth parameters and possible effect of tagging on growth. 相似文献
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Classical methods based on Gaussian likelihood or least-squares cannot identify non-invertible moving average processes, while recent non-Gaussian results are based on full likelihood consideration. Since the error distribution is rarely known a quasi-likelihood approach is desirable, but its consistency properties are yet unknown. In this paper we study the quasi-likelihood associated with the Laplacian model, a convenient non-Gaussian model that yields a modified L 1 procedure. We show that consistency holds for all standard heavy tailed errors, but not for light tailed errors, showing that a quasi-likelihood procedure cannot be applied blindly to estimate non-invertible models. This is an interesting contrast to the standard results of the quasi-likelihood in regression models, where consistency usually holds much more generally. Similar results hold for estimation of non-causal non-invertible ARMA processes. Various simulation studies are presented to validate the theory and to show the effect of the error distribution, and an analysis of the US unemployment series is given as an illustration. 相似文献
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