Department of Linguistics, Northwestern University, Evanston, IL, USA.
Cogn Neuropsychol. 2011 Oct;28(7):451-65; discussion 515-20. doi: 10.1080/02643294.2012.675319.
Using empirical data to develop theories requires not only evaluating how well a theory accounts for data; it requires using the data to select the best theory from among a set of alternatives. Current case series research is examined in light of these two issues. Theory selection requires that theories make contrasting predictions. In the first section of this commentary, I present novel simulation results showing that existing theories of language production do not make contrasting predictions for the overall distribution of responses over a set of responses categories (e.g., correct response, semantic error, etc.; Dell, Schwartz, Martin, Saffran, & Gagnon, 1997). Given such results, in order to be theoretically productive case series research must focus on those aspects of data that serve to contrast theoretical alternatives. The second section considers evaluation of claims regarding individual differences. Such claims are typically underconstrained. Two approaches to addressing this issue are discussed. I argue that case series research should provide independent evidence for hypothesized individual differences. Second, parametric approaches might provide a means of constraining theories of individual differences. The plausibility of this approach is examined through novel analyses of empirical distributions of individual differences in impairments to lexical access (Schwartz, Dell, Martin, Gahl, & Sobel, 2006).
使用经验数据来发展理论不仅需要评估一个理论在多大程度上解释了数据，还需要利用这些数据从一组替代理论中选择最佳理论。本文根据这两个问题来检验当前的病例系列研究。理论选择要求理论做出对比预测。在本评论的第一部分，我提出了新的模拟结果，表明现有的语言产生理论并没有对一组反应类别（例如，正确反应、语义错误等）中的反应分布做出对比预测（Dell、Schwartz、Martin、Saffran 和 Gagnon，1997）。鉴于这些结果，如果要在理论上具有创新性，病例系列研究必须关注那些能够对比理论替代方案的数据方面。第二部分考虑了对个体差异的评估。此类说法通常没有充分的依据。讨论了两种解决这个问题的方法。我认为，病例系列研究应该为假设的个体差异提供独立的证据。其次，参数方法可能为个体差异的理论提供一种约束手段。通过对词汇访问障碍的个体差异的经验分布进行新的分析，检验了这种方法的可行性（Schwartz、Dell、Martin、Gahl 和 Sobel，2006）。
