This paper shows how researchers can make incorrect interpretations of models that include heterogeneity in error variance (scale) if they do not recognize the implications of parameter estimates being conflated with scale. The research contribution is to define best practice management of scale heterogeneity in discrete choice experiments and to empirically demonstrate issues that arise when best practice is ignored. We illustrate the problem using data from two discrete choice experiments, showing that reported parameters vary due to arbitrary normalization decisions. We report examples of papers where authors fall into this trap, potentially leading to erroneous evaluation of models. (JEL C52, Q51)

中文翻译：

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尺度异质性及其对离散选择分析的影响

本文展示了如果研究人员没有认识到参数估计与尺度相混淆的含义，他们如何对包含误差方差（尺度）异质性的模型做出错误解释。研究贡献是定义离散选择实验中规模异质性的最佳实践管理，并以经验证明忽略最佳实践时出现的问题。我们使用来自两个离散选择实验的数据来说明这个问题，表明报告的参数因任意归一化决策而异。我们报告了作者陷入这种陷阱的论文示例，这可能导致对模型的错误评估。(JEL C52, Q51)