Schwarz W
Z Exp Angew Psychol. 1989;36(1):101-17.
This article presents a random walk model that can be analyzed without recourse to Wald's (1947) approximation, which neglects the excess over the absorbing barriers. Hence, the model yields exact predictions for the absorption probabilities and all mean conditional absorption times. We derive these predictions in some detail and fit them to the extensive data of an identification experiment published by Green et al. (1983). The fit of the model seems satisfactory. The relationship of the model to existing classes of random walk models (SPRT and SSR; see Luce, 1986) is discussed; for certain combinations of its parameters, the model belongs either to the SPRT or to the SSR class, or to both. We stress the theoretical significance of the knowledge of exact results for the evaluation of Wald's approximation and general properties of the several models proposed derived from this approximation.
本文提出了一种随机游走模型，该模型无需借助瓦尔德（1947年）的近似方法即可进行分析，后者忽略了超过吸收壁垒的部分。因此，该模型对吸收概率和所有平均条件吸收时间给出了精确预测。我们详细推导了这些预测结果，并将其与格林等人（1983年）发表的一项识别实验的大量数据进行拟合。该模型的拟合效果似乎令人满意。本文还讨论了该模型与现有随机游走模型类别（序贯概率比检验和序贯抽样检验；见卢斯，1986年）的关系；对于其参数的某些组合，该模型要么属于序贯概率比检验类别，要么属于序贯抽样检验类别，或者两者皆属。我们强调，对于评估瓦尔德近似方法以及由此近似方法得出的几个模型的一般性质而言，精确结果的知识具有理论意义。
