As new concepts and discoveries accumulate over time, theamount of information available to speakers increases as well.One would expect that an utterance today would be more in-formative than an utterance 100 years ago (basing informationon surprisal; Shannon, 1948), given the increase in technol-ogy and scientific discoveries. This prediction, however, is atodds with recent theories regarding information in human lan-guage use, which suggest that speakers maintain a somewhatconstant information rate over time. Using the Google Ngramcorpus (Michel et al., 2011), we show for multiple languagesthat changes in lexical information (a unigram model) are actu-ally negatively correlated with changes in structural informa-tion (a trigram model), supporting recent proposals on infor-mation theoretic constraints.

Recent research has seen a surge in interest in the role of theindividual in sound change processes. Do fast speakers have aunique role in sound change processes? Fast speech leads togreater rates of lenition (reduction). But should it mean thatfast talkers would be more likely to lenite even when speak-ing slowly? In two corpus studies we show that even whenfast talkers speak more slowly they are (a) more likely to omitsegments and (b) more likely to perform variable reduction ofconsonants. This draws attention to habitual speech rate as alikely factor in the actuation of lenition processes.

We present data on convergence in the Switchboard corpus, ad-dressing differences across measures and across speakers. Wemeasured convergence in four characteristics, to test consis-tency in related and unrelated measures: F0 median, F0 vari-ance, speech rate, and odds of the fillers uh and um. Conver-gence was significant in all measures and exhibited variationboth between individuals and within individuals. Most notably,convergence in one measure was not predictive of convergencein other measures, except between closely related measures.The results demonstrate some of the limitations of generaliz-ing convergence results from one measure to other measures.