Re: [R] Help with short time series

From: Dieter Menne <>
Date: Mon 07 Aug 2006 - 19:53:11 EST

Simone Vincenzi <simone.vincenzi <at>> writes:

> Dear R-list,
> I have a statistical problem with the comparison of two short time-series of
> density data in an ecological framework. I have to compare two short time
> series (5 years, one value for each year) of species density data (it is the
> density of fish in two different streams) to test if the two means of the
> five densities are significantly different, so basically if the two mean
> stream-specific fish densities are significantly different.
> I don't think I can use a straight t-test due to the problem of
> autocorrelation and I don't think I can use a repeated measure ANOVA as I
> don't have any replicates.
> Any help would be greatly appreciated.

try something like


This should also give you an estimate if the slopes are different if you test against the simplified model


Since you did not provide a short example data set, this is only approximatively right.

Dieter mailing list PLEASE do read the posting guide and provide commented, minimal, self-contained, reproducible code. Received on Mon Aug 07 19:56:29 2006

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