Dear colleagues,

We would like to take advantage of Dr. Slice's comments about MANOVA to
assess differences among species or biological groups.  There are few
multivariate normality tests available, however it is often common that
Partial Warps (and therefore Relative Warps) from morphological
structures do not fit normality. Thus, we think this is the main reason
why Dr. Slice recommends the non-parametric alternatives for MANOVA.
More specifically our problem is that we obtain different results when
applying either of both parametric and non-parametric MANOVAS.
We are at the moment assessing the relationships between environmental
variables (remote sensing data) and morphological characters (geometric
morphometrics) in a group of Neotropical bats.  Neither of both types of
variables fit normality very well.
However, what currently puzzle us is the fact that the MANOVA performed
in SPSS give us significant differences, while the np-MANOVA in PAST
gives us non significant differences.   The contrast in magnitude
between both p-values is extreme.  We haven’t yet looked at additional
indexes of overlap, confidence or robustness for p-values.
We will be grateful with any comments or suggestions.
Pablo Menendez
Pablo Jarrin



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