On Thu, 7 Aug 1997, John Caron wrote: > I guess I don't understand what you mean by "coordinate system". I assume you refer to my comment on following from John Sheldon: > > > Not applicable..."correlation" does not possess "coordinates" the > > > way we think of them. [rest deleted] My comment was: > > I just want to emphasise my agreement by pointing out that one could > > equally well be considering correlations between different variables at > > the same station. I was merely pointing out that the variable which identifies the variables being correlated (e.g. station, met. measurements) is essentially nominal in nature. It could be a coordinate variable with a string value (e.g. station name, type of measurement (e.g. "annual precip.")). I (perhaps wrongly) got the feeling that some people were trying to re-cast such essentially non-geographic cases into geographic frameworks by adding essentially irrelevant (as far as calculating correlations) geographic hooks in the form of lat/lon coordinate variables. Harvey Harvey Davies, CSIRO Mathematical and Information Sciences, 723 Swanston Street, Carlton, Victoria 3053, Australia Email: harvey.davies@cmis.csiro.au Phone: +61 3 9282 2623 or +61 3 9239 4556 Fax: +61 3 9282 2600