Hi, I have some difficulty in figuring out whether I am doing correct or not.
A brief introduction about the work: It is a light/dark choice test conducted in insect larvae. The response is binary (0- present in dark area, 1-present in light area) and the experiment is run for 15 min, so there are 15 repeated measurements per individual larva at 1 min intervals. The factors which affect this study are Strain (2 levels-G and S), wavelength of light (4 levels-blue, green, UV, red), and starting response at 0 min (two levels- animal present in dark-D or light-L). This is how I think it is nested. Strain nested inside Wavelength, Subject (individual) nested within strain, Starting response within subject, and time within Starting response. The data looks like this: Number Wavelength Strain Subject Startingresponse time (min) 1 Red G 1 L 1 2 Red G 1 L 2 --------------------------------------------------------------------------------------------------------------- --------------------------------------------------------------------------------------------------------------------- 20 Red G 1 L 20 21 Red G 2 D 1 22 Red G 2 D 2 --------------------------------------------------------------------------------------------------------------- ----------------------------------------------------------------------------------------------------------------------- 40 Red G 2 D 20 ----------------------------------------------------------------------------------------------------------------- ---------------------------------------------------------------------------------------------------------------- 121 Green G 7 D 1 122 Green G 7 D 2 ------------------------------------------------------------------------------------------------------------------------ --------------------------------------------------------------------------------------------------------------------------- The model I used was: (fm2 <-lmer(Response~Wavelength+Startingresponse+Strain+ time + (time|Subject),family=binomial, data=Behavdat)) I am not sure how to specify the nested structures within the model. Any help will be appreciated. Thanks. [[alternative HTML version deleted]]
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