correlation coefficient
Dieter Menne wrote:
Bert Gunter <gunter.berton <at> gene.com> writes:
Martin's reply provides an appropriate response, so nothing to add. But my
questions dig deeper: Why do so many (presumably nonstatisticians, but ?)
belong to this R^2 religion? Is it because:
1) This is what they are taught in their Stat 101 courses by statisticians?
2) ... by "pseudo"statisticians in their own professions (no disrespect
intended here -- just want to make a clear distinction)?
3) It's the prevailing culture of their discipline (journal requirements,
part of their standard texts, etc.)?
Good point. Speaking from a clinical perspective: It is because many journals (British are the exception) ask medical reviewers to do the statistical reviewing within 5 minutes. They use the following formula to assess the quality of the paper (weights may vary): q(paper) = 10* n(pvalues) + 5*n(R^2) + 3.5*n(Error Bars) Values above 300 qualify for immediate acceptance, and Journals like Lancet, New English and British Journal of XXX provide professional advice. The first two are well known, the last is my special combat area. Glucose values measured every 2 minutes look like lice-comb, and nobody cares about the meaning. Dieter
A very good reply, and the quality formula is probably too close to the truth to be funny. Some of the answers given to the people who petition the list for help seem to loftily ignore the fact that the petitioners are more concerned with getting their paper accepted or their salary paid or their dinner cooked than with the opinions of those not so motivated about the existential significance of R^2. They may, like your humble correspondent, be well aware of the failings of R^2, but be unable to conduct a just and noble campaign against the editor, boss or chef who demands it. I have just returned from a meeting in which the chief investigator was demanding more "user friendliness", despite the fact that this clever marketing ploy had turned much of her previous data to random numbers. I dunno, it beats me. Jim