A robust house price index using sparse and frugal data

In this article, we describe a house price index algorithm which requires only sparse and frugal data, namely house location, date of sale and sale price, as input data. We aim to show that our algorithm is as effective for predicting price changes as more complex models which require detailed or extensive data. Although various methods are employed for determining house price indexes, such as hedonic regression, mix-adjusted median or repeat sales, there is no consensus on how to determine the robustness of an index, and hence no agreement on which method is the best to use. We formalise an objective criterion for what a house price index should achieve, namely consistency between time periods. Using this criterion, we investigate whether it is possible to achieve strong robustness using frugal data covering only 66 months of transactions on the Irish property market. We develop a simple multi-stage algorithm and show that it is more robust than the complex hedonic regression model currently employed by the Irish Central Statistics Office.     

重庆市产业结构与就业结构的变动趋势研究

调整优化产业结构是“十一五规划”的一个重点。通过对重庆市历年经济数据的分析,发现:直辖以来,重庆市的产业结构变动趋势符合三次产业变动规律;就业结构的变动也基本符合配第—克拉克定理,不同的是第三产业吸纳劳动力的能力有逐渐下降,有向第二产业流动的态势。本文具体从结构偏离度、就业弹性、相对劳动生产力等方面进行了分析和论述,以期为重庆市产业结构的调整和优化升级政策的制定和途径选择提供有效的现实依据。     

中国的三大都市圈：辐射范围及差异

本文从新经济地理学中的“中心一外围”理论出发,利用中国城市级面板数据,以港口城市上海、香港、天津为中心的三大都市圈为研究对象,考察了城市在都市国内的地理区位与该城市人均GDP的关系。研究发现,珠三角与长三角都市圈内的城市经济发展水平与到大港口距离间存在“一型”的三次曲线关系。在到大港口的一定距离范围内,集聚力超过离散力,距离核心城市越远,人均GDP越低,但当距离远到一定程度时,离散力就越来越强,出现人均GDP的第二个局部高点。因此,“一型”曲线的第一个谷底点以内的区域就可以作为都市圈的辐射范围,而曲线第一段地理与人均GDP的负相关系数则可以作为核心城市的相对集聚力的度量。本文的主要发现是,长三角都市圈核心城市上海的辐射范围和集聚特性要稍强于珠三角都市圈,而环渤海湾都市圈暂时仍然是多个港口城市共同起到辐射作用的城市体系。     

北京市基础设施承载力指数与承载状态实证研究

本文通过构建基础设施承载力指标体系,对北京市1986-2006年间基础设施承载状态进行了测度,采用主成分分析法计算基础设施承载力指数,并使用相对资源承载能力测度方法测度基础设施承载状态.进而,对北京市各区县2007年基础设施承载力进行了聚类分析,并提出相应政策建议.     

Seniority bias in a tournament

The paper presents a model where the probability of promotion tends to increase with seniority (overall labor market experience) without relying on the accumulation of general human capital. To this end, we consider the optimal design of a tournament (a relative compensation scheme) between two agents with different time horizon, the young and the old, in an overlapping generations framework. When the principal can only imperfectly monitor each agent’s effort level, the difference in time horizon leads to the ex post difference in the marginal value of effort between the two agents. In this case, the optimal tournament necessarily involves a bias towards the old agent. Within this framework, we also examine the relationship between: (1) the monitoring accuracy and the optimal bias; and (2) the value of outside options and the optimal bias.     

测度货币政策地区效应:相对指数及其应用

以往的货币政策效应研究都是建立在假设各地区同质的基础上,着重从宏观总量角度,使用VAR模型分析货币政策的冲击。这种研究有利于突出重点,简化分析。但实际上,各地区的异质性以及VAR模型的内在局限性,可能导致结论不稳健。为克服这些不足,本文尝试从货币政策地区效应的微观基础进行研究,提出衡量货币政策地区效应的相关指标,进而建立测度货币政策地区效应的相对指数,并应用于1998~1999年省际货币政策效应的分析,结果发现,货币政策在通货紧缩的1998~1999年仍然有效,而且货币政策效应从大到小依次为东部、中部、西部。     

Relative consumption, relative wealth and growth

In a growth model where individuals care about their social status measured both by consumption and wealth comparisons, we show that status comparison in wealth heightens economic growth, while status comparison in consumption may affect negatively economic growth.     

International trade and renewable resources under asymmetries of resource abundance and resource management

This paper examines the interaction between relative resource abundance and resource management regimes in determining trade patterns and gains from trade in a two-country model with a renewable resource. A model developed by Brander and Taylor [Brander JA, Taylor MS (1997b) Resour Energy Econ 19:267–297] is extended. It is shown that relative resource abundance determines trade patterns if resource abundance is similar in both countries and the relative demand for the resource good is moderate, or if resource abundance is sufficiently different and the relative demand is not so high. Otherwise, a difference in resource management regimes determines trade patterns. Even under an open-access regime, the resource-scarce country gains from trade unless resource abundance is similar and the relative demand is low.      

Robust Likelihood Methods Based on the Skew-t and Related Distributions

The robustness problem is tackled by adopting a parametric class of distributions flexible enough to match the behaviour of the observed data. In a variety of practical cases, one reasonable option is to consider distributions which include parameters to regulate their skewness and kurtosis. As a specific representative of this approach, the skew‐t distribution is explored in more detail and reasons are given to adopt this option as a sensible general‐purpose compromise between robustness and simplicity, both of treatment and of interpretation of the outcome. Some theoretical arguments, outcomes of a few simulation experiments and various wide‐ranging examples with real data are provided in support of the claim.     

About handy, handmade and handsome models

Statistical inference deals with natural variation between units and with uncertainty due to sampling, measurement error and random assignment to treatments. Almost always it does so within one model, assumed fixed and valid. Here, however, variation of conclusions due to variation in model choice will be discussed. Heuristics to find appropriate models are seldom taught, and model fit tests and model fit diagnostics are far from optimal. The use of more than one model for the same data is illustrated by examples from Item Response Theory.