[R-sig-ME] contradictory odds ratios--a problem with the equation or the interpretation?
john@th@n@jone@ @end|ng |rom gm@||@com
Tue May 11 03:41:58 CEST 2021
Good suggestions and notes here, thanks all for taking the time. It
amounted to a very well-rounded accounting.
*Mitchell*, yes, this makes sense.
*John*, thanks for the questions. Yes, these are from a designed
experiment. Results were all as expected (from descriptives to inferentials
and the Rasch analysis) until this mixed methods output was produced. Of
note, I’m surprised that uneven levels matter for mixed models. It was my
understanding mixed models were flexible and robust enough to deal with
this kind of thing. I have omitted other explanatory factors which “broke”
R and wouldn’t converge (vowel duration was address in item random effects;
word familiarity was explained by association), but I think the most
important predictors remain—at least the ones which address my research
question. Thanks for the suggestion for checking the matrix correlations.
*Ben*, yes, very small differences in outputs for the languages. I’m not
sure I quite follow you here:
“If you look at the participant-by-participant predictions (i.e. including
both the language group and the participant-level random effect in the
prediction) do the results make more sense?”
Do you mean something like this: Y ~ iso1 + iso2 + language + association +
(language|participant) + (1|item)?
Removing language as a predictor is a possibility. As you mentioned, a lot
of that variation is covered by participant and language isn’t key to my
research question. This results in a drastically reduced intercept (3.48,
CI 2.08-5.84), but a higher AIC (2266 vs 2299). How much relative weight
does each carry? Is there literature on this? I may simply use the Mandarin
group to keep things clean (results are solid in doing this).
To the “tangential worry”, yes, the predictors iso1 and iso2 are
continuous, but the confidence interval doesn’t make sense. (It does seem
reasonable when language is removed as a predictor, however).
For association, participants’ associations aren’t correct or incorrect. It
simply indicates whether the participant associated the target word (a word
of interest to me, but unknown to them at the time) with the sentence. E.g.
“really” vs “rarely”; I ___ enjoy family gatherings. Which is correct?
Neither, but many people will associate one over the other. Results are
showing that participants are “hearing” the word they associate with the
context rather than the word that is said. (This correspondingly explains
why odds ratios are so high for when the target word is the same as the one
participants associate with the context.).
All the best,
E: johnathan.jones using gmail.com
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