A Discussion of “Using Angler Characteristics and Attitudinal Data to Identify Environmental Preference Classes: A Latent-Class Model”

In the current issue of Environmental and Resource Economics, Morey et al. (2006) discuss a new approach to using attitudinal data in latent class modeling. We compare this approach with the one taken in Boxall and Adamowicz (2002), in the context of a discrete choice, random utility framework with heterogeneous preferences. We derive the respective likelihood functions of the two approaches to show that they are structurally similar, and discuss their implications for the use of attitudinal data. We conclude with a discussion comparing the relative merits of latent class and random parameters (mixed logit) modeling, offering the view that as a practical matter, choosing between them depends on the analyst’s judgment about the correlation of preference parameters.     

Scale effects in endogenous growth theory: an error of aggregation not specification

Modern Schumpeterian growth theory focuses on the product line as the main locus of innovation and exploits endogenous product proliferation to sterilize the scale effect. The empirical core of this theory consists of two claims: (i) growth depends on average employment (i.e., employment per product line); (ii) average employment is scale invariant. We show that data on employment, R&D personnel, and the number of establishments in the US for the period 1964–2001 provide strong support for these claims. While employment and the total number of R&D workers increase with no apparent matching change in the long-run trend of productivity growth, employment and R&D employment per establishment exhibit no long-run trend. We also document that the number of establishments, employment and population exhibit a positive trend, while the ratio employment/establishment does not. Finally, we provide results of time series tests consistent with the predictions of these models.     

Efficiency and Global Scale Characteristics on the “No Free Lunch” Assumption Only

In a production technology, the type of returns to scale (RTS) associated with an efficient decision making unit (DMU) is indicative of the direction of marginal rescaling that the DMU should undertake in order to improve its productivity. In this paper a concept of global returns to scale (GRS) is developed as an indicator of the direction in which the most productive scale size (MPSS) of an efficient DMU is achieved. The GRS classes are useful in assisting strategic decisions like those involving mergers of units or splitting into smaller firms. The two characterisations, RTS and GRS, are the same in a convex technology but generally different in a non-convex one. It is shown that, in a non-convex technology, the well-known method of testing RTS proposed by Färe et al. is in fact testing for GRS and not RTS. Further, while there are three types of RTS: constant, decreasing and increasing (CRS, DRS and IRS, respectively), the classification according to GRS includes the fourth type of sub-constant GRS, which describes a DMU able to achieve its MPSS by both reducing and increasing the scale of operations. The notion of GRS is applicable to a wide range of technologies, including the free disposal hull (FDH) and all polyhedral technologies used in data envelopment analysis (DEA).     

Tax collection lags and the revenue-maximising inflation

When tax payments take place with a considerable time lag, inflation erodes part of their real value, and this loss may be comparable or even surpass the well-known gains from seigniorage. The paper finds that for the economy of Greece, a reduction of inflation will actually raise the total sum of tax collection and seigniorage, thus easing and not aggravating the debt-accumulation process.     

Employment growth and innovation at the firm level

We analyze the influence of innovation on growth rates of employment in 859 Dutch manufacturing firms over the period 1983–1988. Whereas the (growth of the) R&D intensity of firms has a slightly negative impact on employment, we find that firms with a high share of product-related R&D (as a proxi of R&D related to industrial activities in an early stage of the life cycle) experienced an above average growth of employment. The same holds for firms which directed their R&D towards information technology. Smaller firms have, ceteris paribus, substantially higher growth rates of employment than their larger counterparts. Against our expectations, R&D cooperation has no significant impact on employment growth. The same holds for activities in the fields of biotechnology and new materials.     

新时期高校党建工作的探索与实践——构建学生党员班主任新机制

依据高等学校思想政治教育工作现状、构建学生党员班主任机制的现实意义和理论基础,提出构建学生党员班主任机制有利于充分调动广大学生党员的积极性和主动性,最大限度地挖掘和发挥他们的潜能,切实发挥学生党员作用,有利于高等学校思想政治教育工作的顺利开展。     

Estimating the Weight Undersize Distribution for the Wicksell problem

In Wicksell's corpuscle problem one is interested in estimating the distribution of sphere diameters from the diameters of circle profiles obtained by a random section of the body containing the sphericle particles. The problem is known to be an ill posed inverse problem. Several regularization techniques have been applied to find solutions. We will review some of these in this article. In practical situations one often is more interested in the distribution of weight rather than the distribution of diameters. In estimating the weight undersite distribution similar problems are encountered. We will consider an estimator that is obtained by smoothing the distribution function of the circle diameters locally. It will be shown how the bandwidth must be chosen to obtain consistency and mean square error optirnality. Also asymptotic normality will be shown.     

关于我国城镇最佳规模的实证检验

关于城镇最佳规模问题,在我国学术界和政府部门一直存在争议.通过对相关理论分歧的归纳和西方学者关于最佳城镇规模研究的梳理,借鉴英国学者巴顿(K.J.Buton)的理论,运用我国的城市统计资料构建计量模型,分别从行政管理角度最佳、市民角度最佳和企业生产角度最佳三个方面,实证检验了我国最佳的城镇人口规模.相关结论对于正确选择我国的城市化道路,推动政府部门合理规划城市发展,具有一定的参考价值.     

最佳城市规模理论的三种研究方法

传统的最佳城市规模理论的研究方法主要是成本收益法和经验研究法,成本收益法理论上是合理的,但应用性相对较弱,经验研究法结论丰富,但一定程度上忽视了城市化经济与地方化经济的关联性.最新的城市环境法,依据相关的测度指标,通过对经济、社会、环境的相互作用的研究来确定最佳城市规模.