difference between Kurtosis and Skewness???
TomZ
I am trying to find out what the difference between Kurtosis and
Skewness is. I haven't found any information on the internet.
Do you have an idea where I could find an aricle on that in the
inertnet?
ciao
tomZ
Rick Oliver
A measure of the asymmetry of a distribution. The normal distribution is
symmetric, and has a skewness value of zero. A distribution with a
significant positive skewness has a long right tail. A distribution with a
significant negative skewness has a long left tail. As a rough guide, a
skewness value more than twice it's standard error is taken to indicate a
departure from symmetry.
Kurtosis
A measure of the extent to which observations cluster around a central
point. For a normal distribution, the value of the kurtosis statistic is 0.
Positive kurtosis indicates that the observations cluster more and have
longer tails than those in the normal distribution and negative kurtosis
indicates the observations cluster less and have shorter tails.
In practical terms, skewness is probably more important than kurtosis, and
positive skew is probably more common than negative skew. Most variables
with a fixed lower limit but no fixed upper limit (for example, income --
assuming income can't be less than 0) will tend to be positively skewed.
"TomZ" <ba...@junglebook.disney> wrote in message
news:3a3e039c...@news.unimaas.nl...
Rich Ulrich
And you have done, WHAT, exactly, in
conducting your search?
www.google.com search on skewness kurtosis.
or you could look in my stats-FAQ where there might be something.
--
Rich Ulrich, wpi...@pitt.edu
TomZ
>Positive kurtosis indicates that the observations cluster more and have
>longer tails than those in the normal distribution
wait a minute, if they cluster more how can they have a longer tail???
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the first one clusers more around the mean, it has shorter tails !!!
There is something wrong.
ciao
tomZ
Rich Ulrich
>
> >Positive kurtosis indicates that the observations cluster more and have
> >longer tails than those in the normal distribution
>
> wait a minute, if they cluster more how can they have a longer tail???
>
Positive versus negative:
- the density-curve with the PEAK in the center is also the curve
with long tails.
- the contrasting curve is the one with "shoulders" (so to speak).
Phil Loseth
Check out the glossary of StatSoft's online statistics textbook.
http://www.statsoft.com/textbook/glosfra.html
Phil L
To reply by e-mail, remove KILLJUNK from address.
arun...@gmail.com
Thank you