H. Jacqmingadda et al., TESTS OF GEOGRAPHICAL CORRELATION WITH ADJUSTMENT FOR EXPLANATORY VARIABLES - AN APPLICATION TO DYSPNEA IN THE ELDERLY, Statistics in medicine, 16(11), 1997, pp. 1283-1297
We propose a test of correlation of the residuals in generalized linea
r models which is a generalization of the spatial autocorrelation test
based on Moran's I. It allows adjustment for sizes of geographical ar
eas and for explanatory variables. A formula is given to compute the w
eights according to the alternative hypothesis. We compare inference u
sing the distribution in the model and using the permutation distribut
ion. A simulation study showed that the model-based test may be very c
onservative and this leads to a loss of power compared to the permutat
ion test or to the model-based test with correction for estimated para
meters. As this latter is intractable for very large samples when the
model includes explanatory variables, we recommend the use of the perm
utation test. The permutation test is used to study geographical corre
lation of dyspnoea in the elderly. (C) 1997 by John Wiley & Sons, Ltd.