The uniform information density (UID) hypothesis posits a preference among
language users for utterances structured such that information is distributed
uniformly across a signal. While its implications on language production have
been well explored, the hypothesis potentially makes predictions about language
comprehension and linguistic acceptability as well. Further, it is unclear how
uniformity in a linguistic signal -- or lack thereof -- should be measured, and
over which linguistic unit, e.g., the sentence or language level, this
uniformity should hold. Here we investigate these facets of the UID hypothesis
using reading time and acceptability data. While our reading time results are
generally consistent with previous work, they are also consistent with a weakly
super-linear effect of surprisal, which would be compatible with UID's
predictions. For acceptability judgments, we find clearer evidence that
non-uniformity in information density is predictive of lower acceptability. We
then explore multiple operationalizations of UID, motivated by different
interpretations of the original hypothesis, and analyze the scope over which
the pressure towards uniformity is exerted. The explanatory power of a subset
of the proposed operationalizations suggests that the strongest trend may be a
regression towards a mean surprisal across the language, rather than the
phrase, sentence, or document -- a finding that supports a typical
interpretation of UID, namely that it is the byproduct of language users
maximizing the use of a (hypothetical) communication channel.

本文研究了统一信息密度假说对于语言理解和语言可接受性的影响，使用阅读时间和可接受性数据，发现信息密度的不均匀性会降低可接受性，而统一信息密度假说可以部分解释语言压缩的趋势。