公共管理研究中实验方法的应用:质疑与辨析

An Analysis of Concerns about Applying Experimental Methods in Public Administration Research

近年来公共管理的实验研究迅速崛起,但同时不少学者对于实验方法在公共管理研究领域的应用仍然存在质疑。本文针对实验方法的外部效度困境以及有关实验方法优劣势的认知偏差和误区进行了系统分析。这些分析表明,外部效度对实验研究而言是一个需要回答的问题而非一个标准;实验研究的非现实性有其存在的合理性,而其推广性则主要体现在理论的推广而非研究发现的推广上;对于外部效度的质疑主要针对个别类型的实验方法,不同类型的实验方法有其各自的优劣势;人们对于实验方法优劣势的模糊认知主要来自不同程度的知识盲点和角度差异。

In recent years,experimental m ethods have been brought into focus in public administ ration(PA)research.Althoughthe number of publications on experimental research has been increasing in international PA journals,there are still concerns about applyingexperimental methods in PA research.This article responds to these concerns.It aims to provide PA scholars with a better understanding of the value and the critiques of experimental methods so as to help PA scholars better judge how to apply experimental methods.Specifically,the article first defines the concepts of internal validity and external validity i n experimental research and analyzes their relationship.Then it systematically analyzes the general concerns about the external validity of experimental research.The analysesfocus on two areas,namely,the"lack of realism"and the"lack of generalizability".More specifically,the"lack of realism"is analyzed based on three dime nsions:the physical environment,the research setting,and the observed behavior.The"lack ofgeneralizability"is analyzed based on two dimensions:the issue of realism andrep resentation of the subjects.The analyses revea l that concerns about the external validityof experiments are mainly about certain typesof experiments.Accordingly,the article further discusses the strength and limits of three types of experiments:lab exper iments,field experiments,and survey experiments.Lastly,based on a survey of more than 100 PA scholars and students at a PA methodological camp,the article analyzes someambiguous perceptions of the(dis)advantages of experimental methods,including:Is experimental research out oftouch with reality or is it more realistic?Are the variables in experimental research controllable or uncontrollable?Are the costs of conducting experime ntal research high or low?Can experimental research be replicated or not?The analysesshow that internal validity is the sine qua non of experimental research,whereas experimental validity is never a completely answerable question.The lack of realism is justifiable due to the unique function of experiments.The generalizability of experimental re search is mainly about the generalizability of theory rather than about the generalizability offindi ngs.Fie ld experiments and survey e xperiments can compensate for the lack of realis mand thelack of generalizability in labexperiments.All types of experiments have theirown strengths and limits.The ambiguous perceptions of the(dis)advantages of experimental methods mainly result from a lack of comprehensive knowledge about experimental methods.