Validity — the quest for reality in quantitative and qualitative research

It has been argued that fundamentally different methodological approaches have made for ‘two sociologies’. This view has obscured the fact that the problem of validity has to be tackled independently of any specific methodological premises because of the textuality of sociological data. This does not necessarily imply, however, a single, unified strategy for validity testing. In this paper, some basic theoretical presuppositions underlying the approach to validity testing in quantitative research will be contrasted with the strategies offered by Max Weber's methodological writings on the ideal type. It is argued that the use of ideal typical constructs in qualitative research (exemplified by patient's illness careers) allows systematic validity testing despite the important differences in the conceptualization of social reality which is used in quantitative research, thus serving the purpose of any empirical sociological research, that is, to gain valid insight into societies' concrete reality.     

Thermodynamics and process analysis for future economic scenarios

Economists are increasingly interested in forecasting future costs and benefits of policies for dealing with materials/energy fluxes, polluting emissions and environmental impacts on various scales, from sectoral to global. Computable general equilibrium (CGE) models are currently popular because they project demand and industrial structure into the future, along an equilibrium path. But they are applicable only to the extent that structural changes occur in or near equilibrium, independent of radical technological (or social) change. The alternative tool for analyzing economic implications of scenario assumptions is to use Leontief-type Input-Output (I-O) models. I-O models are unable to endogenize structural shifts (changing I-O coefficients). However, this can be a virtue when considering radical rather than incremental shifts. Postulated I-O tables can be used independently to check the internal consistency of scenarios. Or I-O models can be used to generate scenarios by linking them to econometric macro-drivers (which can, in principle, be CGE models). Explicit process analysis can be integrated, in principle, with I-O models. This hybrid scheme provides a natural means of satisfying physical constraints, especially the first and second laws of thermodynamics. This is important, to avoid constructing scenarios based on physically impossible processes. Process analysis is really the only available tool for constructing physically plausible alternative future I-O tables, and generating materials/energy and waste emissions coefficients. Explicit process analysis also helps avoid several problems characteristic of pure CGE or I-O models, viz. (1) aggregation errors (2) inability to handle arbitrary combinations of co-product and co-input relationships and (3) inability to reflect certain non-linearities such as internal feedback loops.     

Public pricing of final and intermediate goods in the presence of externalities

The purpose of this paper is to investigate the impact of externalities on pricing decisions by a public or a private regulated firm selling both final and intermediate goods. The externalities generate feedbacks in demand that affect both consumers and producers. The model is very general in that it does not impose constant returns to scale on private production, allows for distributional effects of both the publicly determined prices and private sector profits, and captures the general equilibrium effects of public pricing. Socially optimal pricing rules are derived, and the relation of the results with previous models of pricing in the presence of externalities is investigated.     

基于成本的物流中心优化设计研究

如何有效地优化物流中心布局设计 ,以便在控制成本的同时提升产品的附加值 ,是众多企业面临的一个共同问题。本文从物流中心设置及配送方案着手 ,提出了相关的优化方法以期解决这一问题。     

Modeling Cyclical Asymmetries in European Imports

This paper applies smooth transition models to capture the nonlinear behavior in the imports data of six major European economies and to assess whether such nonlinearities are related to business cycle asymmetries. Two classes of switch between regimes are considered: endogenously determined transition that assumes nonlinearities are generated by idiosyncratic components specific to foreign trade, and exogenous transition based on GDP growth as a more direct indicator of the cyclical state of the economy. The results support the proposition that the dynamics of imports are nonlinear. In Belgium, France, Spain, and the United Kingdom, regimes change over the business cycle, while in Germany and Italy the switch between regimes is endogenous. National characteristics play a role in defining the position of extreme regimes, the smoothness of the transition, and local dynamics within each state.Previous versions of this article have been presented at the 57th International Atlantic Economic Conference (Lisbon, Portugal, March 10–14, 2004) and at the VII Encuentro de Economía Aplicada (Vigo, Spain, June 3–5, 2004). The authors thank the conference participants and an anonymous referee for their comments.     

The Exchange Rate and its Fundamentals in a Complex World

We develop a nonlinear exchange rate model with heterogeneous agents. Some agents adopt a “fundamentalist” forecasting rule, while others use a “chartist” forecasting rule. We show that the model is capable of explaining the empirical puzzles relating to exchange rate movements. In particular, the model explains the “exchange rate determination” and PPP puzzles, the excess volatility, and fat tails in exchange rate returns.     

Why Punish? Social reciprocity and the enforcement of prosocial norms

Recently economists have become interested in why people who face social dilemmas in the experimental lab use the seemingly incredible threat of punishment to deter free riding. Three theories with evolutionary microfoundations have been developed to explain punishment. We survey these theories and use behavioral data from surveys and experiments to show that the theory called social reciprocity in which people punish norm violators indiscriminately explains punishment best.JEL Classification: C91, C92, D64, H41 Correspondence to: Jeffrey P. CarpenterWe thank Carolyn Craven, Corinna Noelke and two referees for comments, and Middlebury College for financial assistance. In addition, Carpenter acknowledges the support of the National Science Foundation (SES-CAREER 0092953).     

Sectoral Energy- and Labour-Productivity Convergence

This paper empirically investigates the development of cross-country differences in energy- and labour productivity. The analysis is performed at a detailed sectoral level for 14 OECD countries, covering the period 1970–1997. A σ-convergence analysis reveals that the development over time of the cross-country variation in productivity performance differs across sectors as well as across different levels of aggregation. Both patterns of convergence as well as divergence are found. Cross-country variation of productivity levels is typically larger for energy than for labour. A β-convergence analysis provides support for the hypothesis that in most sectors lagging countries tend to catch up with technological leaders, in particular in terms of energy productivity. Moreover, the results show that convergence is conditional, meaning that productivity levels converge to country-specific steady states. Energy prices and wages are shown to positively affect energy- and labour-productivity growth, respectively. We also find evidence for the importance of economies of scale, whereas the investment share, openness and specialization play only a modest role in explaining cross-country variation in energy- and labour-productivity growth.