Busting a myth with the Bayes Factor: Effects of letter bigram frequency in visual lexical decision do not reflect reading processes

Psycholinguistic researchers identify linguistic variables and assess if and how these affect cognitive processes. One such variable is letter bigram frequency, or the frequency with which a given pair of letters co-occurs in an orthography. While early studies have shown that bigram frequency affects visual word recognition, subsequent, well-controlled studies have failed to show such an effect. Still, researchers continue to use it as a control variable in psycholinguistic experiments. We propose two reasons for the persistence of this variable: (1) Studies have reported no evidence for an effect of bigram frequency, but this cannot provide evidence for no effect. (2) The theoretical implications of a bigram frequency have been largely neglected. We address the first issue by performing Bayes Factor tests on both a matched item set and large-scale studies, and the second by discussing possible theoretical implications. We find no effects of bigram frequency effects for lexical decisions, though there is some evidence for an effect in reading aloud.

心理语言学研究者在识别语言变量并评估其如何影响认知过程方面发挥着重要作用。其中一种变量是字母二元频率，即给定的一对字母在一个正字法中共同出现的频率。尽管早期研究表明二元频率会影响视觉词汇识别，但随后的严格控制研究未能证实这一效应。然而，研究人员仍将其作为心理语言实验中的控制变量。我们提出两个原因来解释这一变量的持续存在：（1）研究未发现二元频率有影响的证据，但这并不能提供无影响的证据。（2）二元频率的理论意义在很大程度上被忽视。我们针对第一个问题通过对匹配项目集和大规模研究进行贝叶斯因子测试，针对第二个问题通过讨论可能的理论意义来应对。我们发现，在词汇决策中，二元频率没有产生任何影响，尽管在朗读时存在一些影响的证据。