Tanno Takayuki
Department of Psychology, Meisei University, Hodokubo 2-1-1, Hino, Tokyo 191-8506, Japan.
Behav Processes. 2016 Nov;132:12-21. doi: 10.1016/j.beproc.2016.09.001. Epub 2016 Sep 13.
The purpose of this study was to analyze the response pattern difference between variable-ratio (VR) and variable-interval (VI) schedules of reinforcement by modeling interresponse time distributions of rats' lever presses. All eight rats showed higher response rates under VR 30 than under inter-reinforcement intervals yoked VI. The 30 models consisting of single Exponential (with and without the lower limit on interresponse times), Weibull, Normal, Log-Normal or Gamma distributions, all possible two component combinations of those, and 3 and 4 component models consisting of Weibull, Normal, Log-Normal, or Gamma distribution combinations were compared. The 4 component Log-Normal model was the best in terms of the Akaike information criterion and visual inspection of fitting outcome. Parameter estimates for the L4 model showed that the VR-VI response rate difference is due to a difference in short interresponse times or within bout responses. This results suggests that the VR-VI response rate difference is not an indication of a difference in the overall tendency to respond but it is rather a difference in terms of what types of response patterns are engendered between the two schedules.
本研究的目的是通过对大鼠杠杆按压的反应间隔时间分布进行建模，分析可变比率（VR）和可变间隔（VI）强化程序之间的反应模式差异。所有八只大鼠在VR 30条件下的反应率均高于与其强化间隔匹配的VI条件下的反应率。对由单一指数分布（有和没有反应间隔时间下限）、威布尔分布、正态分布、对数正态分布或伽马分布组成的30种模型，以及由这些分布的所有可能的双组分组合，以及由威布尔分布、正态分布、对数正态分布或伽马分布组合组成的三组分和四组分模型进行了比较。就赤池信息准则和拟合结果的视觉检查而言，四组分对数正态模型是最佳的。L4模型的参数估计表明，VR-VI反应率差异是由于短反应间隔时间或单次反应序列内反应的差异所致。这一结果表明，VR-VI反应率差异并非表明整体反应倾向存在差异，而是表明两种强化程序所产生的反应模式类型存在差异。
