On the predictive validity of various corpus-based frequency norms in L2 English lexical processing.

The predictive validity of various corpus-based frequency norms in first-language lexical processing has been intensively investigated in previous research, but less attention has been paid to this issue in second-language (L2) processing. To bridge the gap, in the present study we took English as a case in point and compared the predictive power of a large set of corpus-based frequency norms for the performance of an L2 English visual lexical decision task (LDT). Our results showed that, in general, the frequency norms from SUBTLEX-US and WorldLex-Blog tended to predict L2 performance better in reaction times, whereas the frequency norms from corpora with a mixture of written and spoken genres (CELEX, WorldLex-Blog, BNC, ANC, and COCA) tended to predict L2 accuracy better. Although replicated in both low- and high-proficiency L2 English learners, these patterns were not exactly the same as those found in LDT data from native English speakers. In addition, we only observed some limited advantages of the lemma frequency and contextual diversity measures over the wordform frequency measure in predicting L2 lexical processing. The results of the present study, especially the detailed comparisons among the different corpora, provide methodological implications for future L2 lexical research.

Phonetic detail in German syllable pronunciation: influences of prosody and grammar.

This study presents two experiments designed to disentangle various influences on syllable pronunciation. Target syllables were embedded in carrier sentences, read aloud by native German participants, and analyzed in terms of syllable and vowel duration, acoustic prominence, and spectral similarity. Both experiments revealed a complex interaction of different factors, as participants attempted to disambiguate semantically and syntactically ambiguous structures while at the same time distinguishing between important and unimportant information. The first experiment examined German verb prefixes that formed prosodic minimal pairs. Carrier sentences were formulated so as to systematically vary word stress, sentence focus, and the type of syntactic boundary following the prefix. We found clear effects of word stress on duration, prominence, and spectral similarity as well as a small influence of sentence focus on prominence levels of lexically stressed prefixes. While sentence boundaries were marked by particularly high prominence and duration values, hardly any effect was shown for word boundaries. The second experiment compared German function words which were segmentally identical but appeared in different grammatical roles. Here, definite articles were found to be shorter than relative pronouns and still shorter than demonstrative pronouns. As definite articles are also much more common than the other two lexical classes, effects of lemma frequency might also have played a role.