Economic Analysis of Data from Laboratory Experiments: Endogeniety, Attrition, Subject Heterogeniety, and Interdependencies

这项建议涉及对经济学实验室实验的数据进行统计分析所涉及的若干问题。经济学中的实验工作对该领域的重要性与日俱增，但与现有的机会和提出的研究问题相比，对这些实验数据的统计分析仍然相对原始。我们调查的目的既是方法论的，也是实质性的：方法论的意义是展示现代统计(计量经济学)技术在实验人员主要关心的数据分析问题上的应用，并改进这些技术的应用，以解决实验室实验数据带来的特殊问题(和机会)。实质性的是，所讨论的一些具体问题在文献中是令人关切的，因此，这里提出的新实验和相应的数据分析应该为手头的问题提供新的见解。建议在若干问题上开展工作。(1)在普通价值(或矿业权)拍卖实验中，存在显著的自我选择效应，因为成为赢家诅咒的牺牲品的投标人会赔钱，经常破产，并以很少的钱结束实验。因此，他们倾向于自行选择不返回参加随后的试验性会议，这可能导致就更有经验的投标人的行为得出的结论存在重大偏见。我们的计划是测量偏差，并探索不同的方法来处理它，无论是统计上的还是实验设计上的。(2)经济实验中的一种常见方法是在给定的实验时段内提供重复试验的回报，以向受试者提供有关经济意外情况的经验。这导致受试者随着时间的推移积累实验的收益，而这些收益的影响通常被忽视，或者在研究时无法解释这些收益变化的内生性。这反过来可能导致对拍卖结果的分析出现重大偏差。我们计划在经济理论表明代理人不会受到这种影响的情况下，确定为什么代理人受到这种影响，并扩展开发的实验方法，以研究矿业权拍卖实验中收益对现金余额影响的影响。(3)经济学家长期以来一直怀疑，经济实验的表现至少在一定程度上反映了受试者在实验室以外的经历以及他们的人口统计学特征。我们将通过收集在实地数据统计分析中形成的学科借用方法的相关人口统计和经验数据来系统地研究这一问题。(4)在许多经济实验中，个体受试者观察之间存在潜在的相互依存关系，这与在给定的实验时段内对一组受试者的重复观察有关。我们计划在许多不同的情况下探讨这一问题，并制定处理方法。(5)在对经济实验中的行为进行统计评估时，研究人员通常假设所有或大部分反应系数在不同受试者中都是恒定的。在许多情况下，这很可能是不正确的。我们计划研究如何解释在这种情况下不同个体的反应异质性。

This proposal addresses a number of issues involved in the statistical analysis of data from laboratory experiments in economics. Experimental work in economics is of growing importance to the field, but the statistical analysis of data from these experiments is still relatively primitive compared to the opportunities available and the research issues posed. The purpose of our investigations is both methodological and substantive: Methodological in the sense of demonstrating applications of modern statistical (econometric) techniques to data analysis issues of central concern to experimenters, and refining applications of these techniques to the special questions (and opportunities) that laboratory experimental data pose. Substantive in that a number of the particular issues addressed have been of concern in the literature, so that the new experiments proposed here, and the corresponding data analysis, should provide new insights into the issues at hand. Work is proposed on a number of issues. (1) In common value (or mineral rights) auction experiments there is a significant self-selection effect as bidders who fall prey to the winner's curse lose money, often go bankrupt, and end the experiment with very little money. As a consequence they tend to self-select out of returning for subsequent experimental sessions which can lead to important biases in the conclusions reached regarding the behavior of more experienced bidders. The plan is to both measure the bias and to explore different ways of dealing with it, both statistically and in terms of experimental design. (2) One common method in economic experiments is to provide repeated trials with payoffs within a given experimental session to provide subjects with experience with the economic contingencies involved. This leads to subjects accumulating earnings from the experiment over time whose effect is typically ignored, or when studied fails to account for the endogeneity of changes in these earnings. This in turn can lead to important biases in the analysis of auction outcomes. We plan to determine why agents are subject to such effects when economic theory suggests that they will not be, and to extend the experimental methodology developed to study the impact of earnings on cash balance effects in mineral rights auction experiments. (3) Economists have long suspected that performance in economic experiments reflects, at least in part, the experiences of subjects outside the lab as well as their demographic characteristics. We will study this systematically by collecting relevant demographic and experiential data on subjects borrowing methods developed in the statistical analysis of field data. (4) In many economic experiments there are potential interdependencies between individual subject observations associated with repeated observations of a group of subjects within a given experimental session. We plan to explore this issue in a number of different settings and to devise ways for dealing with it. (5) Often when statistically evaluating behavior in economic experiments investigators assume that all, or most, response coefficients are constant across subjects. This is likely to be incorrect in a number of cases. We plan to study ways of accounting for this response heterogeneity across individuals in such cases.