Kurtosis

1. NADEEM UDDIN
ASSOCIATE PROFESSOR
OF STATISTICS

2. Kurtosis:
Kurtosis is a measure of whether the data are peaked or flat
relative to a normal distribution. That is, data sets with high
kurtosis tend to have a distinct peak near the mean, decline
rather rapidly, and have heavy tails. Data sets with low
kurtosis tend to have a flat top near the mean rather than a
sharp peak. A uniform distribution would be the extreme case.

3. Interpretation of result:
1- If the kurtosis result is less than 3 then the distribution
is platykurtic.
2- If the kurtosis result is 3 then the distribution is
mesokurtic.
3- If the kurtosis result is more than 3 then the
distribution is leptokurtic.

5. EXAMPLE-1
If 𝜇2 = 26 , and 𝜇4 = 1355 find the coefficient of kurtosis.
Solution:
𝛽2 =
𝜇4
𝜇2
2
𝛽2 =
1355
26 2
𝛽2 = 2.00
Comments
Since 𝛽2 < 3, therefore
Distribution is platykurtic.