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I need to do a data analysis in R. My data consists of 2 populations of animals that have 2 different types of genomes. The children are always born as twins. I also know the mothers' weight and the combined weight of the children after 14 days. I want to fit a model that explains the variability of the twins' weights after 14 days.


population 1 and 2
genome 1 and 2
twins both male, both female, one female and one male
mother's weight
twins weight after 14 days

I'm planning to do an ANCOVA, but is there a better analysis I should use?

All suggestions are welcome. Big thanks for the help.

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Welcome to the site. I removed your signature line as the system adds it automatically. – Peter Flom Oct 24 '12 at 10:36
Do you have the individual children's weight or just their combined weight? And can you clarify - when you mean "the variability of the twins' weights" do you mean the variation between each set of twins, or the variation between the two members of each set of twins? – Peter Ellis Oct 25 '12 at 9:13

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