[EMAIL PROTECTED] (Anders D Hojen) wrote in message news:<[EMAIL PROTECTED]>... > [...] > I'm measuring sentence durations to follow up studies on the seemingly > trivial fact that non-native speakers tend to speak more slowly than > native speakers. I'm trying to find the psycholinguistic locus (or loci) > of their slowness. The hypothesis I'm testing is that that locus is > syntactical processing. The between-groups factor is 'group' (native vs. > non-native). The within-group factor is 'syntactic complexity' of the > sentences that the subjects repeated (3 levels). > > In an ANOVA on the raw data, the interaction was significant, and I > found that the mean group difference was not significant for the simple > sentences, but for the complex sentences. Thus, I might infer that > increased syntactic processing load slows non-native talkers down. > > However, syntactic complexity is confounded with sentence length, > because the more complex the syntax of a sentence gets (i.e., the more > words there are), the longer it inevitably gets. The group differences > are larger for complex sentences (say, 2200 vs. 2500 ms) than simple > sentences (say 500 vs. 550 ms). I'm wondering whether the ANOVA went: > "Hey look, a delta of 300 is larger than a delta of 50; I'm gonna output > a significant interaction". Will the ANOVA recognize that the delta of > 50 is based smaller values than the delta of 300? This is why I thought > of z-scores. But maybe they won't make a difference? > [...]
Try analyzing the logs of the durations. Then the anova, which always looks at absolute differences in the numbers it has, will actually be considering relative differences in the original numbers. And you may also get rid of some of the interactions, too. . . ================================================================ This list will soon be replaced by the new list EDSTAT-L at Penn State. Please subscribe to the new list using the web interface at http://lists.psu.edu/archives/edstat-l.html. ================================================================
