Length, frequency, and predictability effects of words on eye movements in reading

TLDR

The study provides a benchmark dataset for computational models of eye‑movement control in reading. The authors examined how word length, frequency, and predictability influence eye‑movement metrics in 144 German sentences read by 33 young and 32 older adults. Length and frequency consistently affected fixation durations and probabilities, predictability mainly influenced probabilities, all three factors impacted target words, low predictability increased rereading, and older adults were slower with more regressions.

Abstract

We tested the effects of word length, frequency, and predictability on inspection durations (first fixation, single fixation, gaze duration, and reading time) and inspection probabilities during first‐pass reading (skipped, once, twice) for a corpus of 144 German sentences (1138 words) and a subset of 144 target words uncorrelated in length and frequency, read by 33 young and 32 older adults. For corpus words, length and frequency were reliably related to inspection durations and probabilities, predictability only to inspection probabilities. For first‐pass reading of target words all three effects were reliable for inspection durations and probabilities. Low predictability was strongly related to second‐pass reading. Older adults read slower than young adults and had a higher frequency of regressive movements. The data are to serve as a benchmark for computational models of eye movement control in reading.