Cheng K, Miceli P
School of Behavioural Sciences, Macquarie University, Sydney, NSW 2109, Australia.
Department of Psychology, University of Toronto, Toronto, Canada.
Behav Processes. 1996 Sep;37(2-3):137-56. doi: 10.1016/0376-6357(95)00083-6.
Computer simulations based on the Scalar Expectancy Theory (SET) and the connectionist model of Church and Broadbent (1990) were run to match data sets from the peak procedure. On the peak procedure, a light or tone usually signals a reward for a response after a fixed interval (FI), but occasionally, the signal is left on for a long time and reward is withheld. On such a test, a period of high rate of responding (run) is sandwiched between periods of low rates of responding. Models were run to match the means and standard deviations of the start, the end, the middle, and the duration of the run, as well as the correlations among them. On a trial, the models based on SET determined the start and the end of the run according to a memory of expected time of reward and one or two thresholds. Models sampling two thresholds, with both difference and ratio comparison rules, fit the data well. In the connectionist models the memory was a matrix of vector autocorrelations, with a vector representing a clock reading on a set of oscillators. The thresholds were each an angle between the clock vector and a comparison vector derived from memory. These models did not fare well.
基于标量期望理论（SET）以及丘奇和布罗德本特（1990）的联结主义模型进行了计算机模拟，以匹配来自峰值程序的数据集。在峰值程序中，通常一个灯光或音调会在固定间隔（FI）后对一种反应发出奖励信号，但偶尔信号会持续很长时间且不给予奖励。在这样的测试中，高反应率时期（运行期）夹在低反应率时期之间。运行模型以匹配运行期的开始、结束、中间阶段以及持续时间的均值和标准差，以及它们之间的相关性。在一次试验中，基于SET的模型根据预期奖励时间的记忆以及一两个阈值来确定运行期的开始和结束。采用差异和比率比较规则、对两个阈值进行采样的模型能很好地拟合数据。在联结主义模型中，记忆是一个向量自相关矩阵，其中一个向量代表一组振荡器上的时钟读数。每个阈值是时钟向量与从记忆中得出的比较向量之间的一个夹角。这些模型表现不佳。
