A local maximum likelihood estimator for Poisson regression

A local maximum likelihood estimator based on Poisson regression is presented as well as its bias, variance and asymptotic distribution. This semiparametric estimator is intended to be an alternative to the Poisson, negative binomial and zero-inflated Poisson regression models that does not depend on regularity conditions and model specification accuracy. Some simulation results are presented. The use of the local maximum likelihood procedure is illustrated on one example from the literature. This procedure is found to perform well. This research was partially supported by Calouste Gulbenkian Foundation and PRODEP III.     

The impact of intellectual property rights protection on trade: The role of a “third country” in market power and market expansion effects

This study analyzes the impact of increased protection of intellectual property rights (IPRs) in importing countries on the inventing countries’ exports in the presence of “third countries.” In this study, “third countries” include all countries that compete with the inventing countries in exporting similar products to the importing countries. The most significant contribution of this study is to develop an alternative empirical approach for analyzing the impact of IPRs on trade flows. This approach considers three players (the inventing/exporting country, the importing country, and “third countries”) and thus is tentatively called the “three-country model.” The findings confirm that our “three-country model” provides important insights into the impact of IPR protection on international trade, especially in the context of increasingly fierce competition in international trade. We found that the emergence of a third country restrains the market power effects and stimulates market expansion effects. Specifically, when a third country appears, the increased protection of IPRs in the importing countries encourages the inventing countries to increase their exports. However, the export elasticity of IPR protection is highest for primary products and lowest for technology-intensive and human capital–intensive products.     

刍议工程招标中拦标价的设立

针对目前工程量清单招标项目中设立拦标价的做法是否合法合理,以及如何准确计算拦标价仍存在一定的争议。论述了拦标价设立的目的、作用、法规依据和造价依据以及拦标价在应用中存在的一些问题,提出了一种基于概率论的知识来确定拦标价上浮比例的方法,并指出拦标价在招标和评标应用中需要注意的问题。     

成都市房价影响因素的回归分析与事后模拟

运用SPSS软件,以GDP、市区居民人均可支配收入、住宅投资完成额、住宅施工面积、住宅竣工面积和市区人口为自变量,采用1997～2005年9年的数据,建立了多元线性回归模型,对成都市房价这一因变量进行了模拟分析。模型通过各种检验,得出了影响成都市住房价格最重要的因素是市区人口和住宅施工面积这一结论;最后,并运用模型做了事后模拟,其结果比较接近市场价格。     

The empirical relevance of the competitive storage model

The empirical relevance of models of competitive storage arbitrage in explaining commodity price behavior has been seriously challenged in a series of pathbreaking papers by [Deaton and Laroque, 1992], [Deaton and Laroque, 1995] and [Deaton and Laroque, 1996]. Here we address their major criticism, that the model is in general unable to explain the degree of serial correlation observed in the prices of twelve major commodities. First, we present a simple numerical version of their model which, contrary to Deaton and Laroque (1992), can generate the high levels of serial correlation observed in commodity prices, if it is parameterized to generate realistic levels of price variation. Then, after estimating the [Deaton and Laroque, 1995] and [Deaton and Laroque, 1996] model using their data set, model specification and econometric approach, we show that the use of a much finer grid to approximate the equilibrium price function yields quite different estimates for most commodities. Results are obtained for coffee, copper, jute, maize, palm oil, sugar and tin that support the specifications of the storage model with positive constant marginal storage cost and no deterioration as in Gustafson (1958a). Consumption demand has a low response to price and, except for sugar, stockouts are infrequent. The observed magnitudes of serial correlation of price match those implied by the estimated model.     

2009年与2007年“地王”叠出比较

本文通过地价这个主要参数,选择比较具有代表性的时点,比较了2007年和2009年这两个时点上"地王"迭出的现象,重点论述了房地产调控的重要性和必要性。     

Fourth order pseudo maximum likelihood methods

We extend PML theory to account for information on the conditional moments up to order four, but without assuming a parametric model, to avoid a risk of misspecification of the conditional distribution. The key statistical tool is the quartic exponential family, which allows us to generalize the PML2 and QGPML1 methods proposed in Gourieroux et al. (1984) to PML4 and QGPML2 methods, respectively. An asymptotic theory is developed. The key numerical tool that we use is the Gauss-Freud integration scheme that solves a computational problem that has previously been raised in several fields. Simulation exercises demonstrate the feasibility and robustness of the methods.     

Relative prices and electronic substitution: Changes in household-level demand for postal delivery services from 1986 to 2004

This paper quantifies the extent to which the shift in the aggregate household-level demand for postal delivery services can be attributed to the appearance of alternative modes of communication versus the concomitant rise in postal prices. We find that both recent postal price increases and the penetration of personal computer technology among US households led to similar reductions in postal expenditure. We further find that a 5% postal price increase, such as the one introduced in January 2006 reduces revenue collected from US households by $215 million and imposes an aggregate welfare loss on US households of $333 million.     

A mixed index approach to identifying hedonic price models

Recent literature suggests identifying house price hedonic regressions by using instrumental variables, spatial statistics, the borders approach, panel data, and other techniques. We present an empirical application of a mixed index model, first proposed by Bowden [Bowden, R.J., 1992. Competitive selection and market data: the mixed-index problem. The Review of Economic Studies 59(3):625–633.] to identify hedonic price regressions. We compare the performance of the mixed index model to a traditional hedonic model and to a hedonic model that includes characteristics of the buyer of each house. We find the mixed index model outperforms the other models based on bootstrap distributions of predicted housing values, prediction variance, and predicted policy effects. The mixed index model distributions are less skewed and kurtotic than the other models, suggesting it more closely satisfies the classical linear regression assumption of normally distributed errors. Compared to the mixed index model, the traditional hedonic overstates the importance of lot size and school quality to house price and understates the importance of environmental quality.     

On the analysis of multivariate growth curves

Growth curve data arise when repeated measurements are observed on a number of individuals with an ordered dimension for occasions. Such data appear frequently in almost all fields in which statistical models are used, for instance in medicine, agriculture and engineering. In medicine, for example, more than one variable is often measured on each occasion. However, analyses are usually based on exploration of repeated measurements of only one variable. The consequence is that the information contained in the between-variables correlation structure will be discarded.  In this study we propose a multivariate model based on the random coefficient regression model for the analysis of growth curve data. Closed-form expressions for the model parameters are derived under the maximum likelihood (ML) and the restricted maximum likelihood (REML) framework. It is shown that in certain situations estimated variances of growth curve parameters are greater for REML. Also a method is proposed for testing general linear hypotheses. One numerical example is provided to illustrate the methods discussed. Received: 22 February 1999     

中国空气质量的价格评估

本文基于中国地级市的房地产市场数据,通过享乐定价方法研究了中国居民对空气质量改善的边际支付意愿。结果显示,平均而言,PM10的年平均浓度每降低一单位（1μg/m3）,居民愿意为商品住房多支付35.91元/m2,相当于同期商品住房价格的0.9%;SO2的年平均浓度每降低一单位（1μg/m3）,居民愿意为商品住房多支付41.65元/m2,相当于同期商品住房价格的1.01%。本文对中国城市的空气质量价值进行了更为准确和全面的评估,并通过对空气质量变化所带来的经济效益及福利损失的估算,为政府治理空气污染的决策制定与制度安排提供了可靠全面的参考。     

THE BIVARIATE EXPONENTIAL DISTRIBUTION; A REVIEW AND SOME NEW RESULTS

Various models have been proposed as bivariate forms of the exponential distribution. A brief but comprehensive review is presented which classifies, interrelates and contrasts the different models and outlines what is known about distributional properties, applicability and estimation and testing of parameters (particularly the association parameter). Some new results are presented for one particular model. Maximum likelihood, and moment–type, estimators of the association parameter are examined. Asymptotic variances are derived and attention is given to the relative efficiency of the estimators and to problems of their evaluation.