You should bootstrap the two groups separately. The bootstrap sample you get do not follow the same order as the original sample, so the first 62 observations are coming from both groups. What you bootstrapped is essentially the difference between the pooled mean and itself, which would no doubt come up as 0. -- View this message in context: http://r.789695.n4.nabble.com/Bootstrap-tp2317776p2318480.html Sent from the R help mailing list archive at Nabble.com.
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