spatial trend and competition

Dear asremlers,

This is probably the wrong list for this question but here goes
anyway:

In asreml3 there is a SAR2 covariance structure which represents
combined spatial trend and competition. There is also an SAR
structure. Does this represent trend with no competition or
competition with no trend (or neither of these)?

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: I.White :
: University of Edinburgh :
: Ashworth Laboratories, West Mains Road :
: Edinburgh EH9 3JT :
: Tel 0131 650 5490 Fax 0131 650 6564 :
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