Re: significance of skewness

Olivier,

Thanks. Looking at the distribution it is certainly not normally
distributed. It is too skewed. I'm not really interested in the real
distribution although this might of course directly indicate whether
I'm dealing with a skewed distribution.

What do you mean with "there are also tests for skewness"? I know that
there are tests that provide a number for the skewness of a
distribution (0 if the distribution is symmetrical). However, even a
set of data generated from a normal distribution will have a skewness
purely by chance. The question is: when do we have a significant
skewness.

At this moment i proceed as follows. I take 10.000 bootstrap samples
from the experimental data and calculate the skweness for each of the
boostrapping samples. The resulting distribution of skewness values
does not include 0, thus i now concluded that the original distribution
has a significant skewness.

Antoine

.

Relevant Pages

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