Department of Psychology, University of Massachusetts, 430 Tobin Hall, Amherst, MA, 01003, USA,
Psychon Bull Rev. 2013 Dec;20(6):1304-11. doi: 10.3758/s13423-013-0444-x.
The present study investigated the relationship between the location and skew of an individual reader's fixation duration distribution. The ex-Gaussian distribution was fit to eye fixation data from 153 subjects in five experiments, four previously presented and one new. The τ parameter was entirely uncorrelated with the μ and σ parameters; by contrast, there was a modest positive correlation between these parameters for lexical decision and speeded pronunciation response times. The conclusion that, for fixation durations, the degree of skew is uncorrelated with the location of the distribution's central tendency was also confirmed nonparametrically, by examining vincentile plots for subgroups of subjects. Finally, the stability of distributional parameters for a given subject was demonstrated to be relatively high. Taken together with previous findings of selective influence on the μ parameter of the fixation duration distribution, the present results suggest that in reading, the location and the skew of the fixation duration distribution may reflect functionally distinct processes. The authors speculate that the skew parameter may specifically reflect the frequency of processing disruption.
本研究调查了个体读者注视持续时间分布的位置和偏度之间的关系。在五个实验中，对来自 153 名被试者的眼动数据进行了 Ex-Gaussian 分布拟合，其中四个是之前呈现的，一个是新的。τ参数与μ和σ参数完全不相关；相比之下，在词汇判断和快速发音反应时间中，这些参数之间存在适度的正相关。通过检查分组被试的百分位图，也可以非参数地证实，对于注视持续时间，偏度的程度与分布中心趋势的位置不相关。最后，还证明了给定被试者的分布参数的稳定性相对较高。综合之前关于注视持续时间分布μ参数的选择性影响的发现，本研究结果表明，在阅读中，注视持续时间分布的位置和偏度可能反映了功能上不同的过程。作者推测，偏度参数可能特别反映了处理中断的频率。
