sturlamolden wrote: > Robert Kern wrote: > >> The difference between the two models is that the first places no >> restrictions >> on the distribution of x. The second does; both the x and y marginal >> distributions need to be normal. Under the first model, the correlation >> coefficient has no meaning. > > That is not correct. The correlation coefficient is meaningful in both > models, but must be interpreted differently. However, in both cases a > correlation coefficient of 1 or -1 indicates an exact linear > relationship between x and y. > > Under the first model ("linear regression"), the squared correlation > coefficient is the "explained variance", i.e. the the proportion of y's > variance accounted for by the model y = m*x + o.
Point. -- Robert Kern "I have come to believe that the whole world is an enigma, a harmless enigma that is made terrible by our own mad attempt to interpret it as though it had an underlying truth." -- Umberto Eco -- http://mail.python.org/mailman/listinfo/python-list