Kurtosis
- calculates kurtosis

Math functions
(AFL 4.20)


SYNTAX Kurtosis( ARRAY, range, population = True )
RETURNS ARRAY
FUNCTION The function calculates Kurtosis.

Kurtosis( ARRAY, range, False ) - works the same as Excel's KURT function

Kurtosis( ARRAY, range, True ) - gives population Kurtosis (Excel does not have equivalent KURT.P function yet)

Note that these functions calculate excess kurtosis, so for normal distribution it is 0.

There is some controversy about what kurtosis really tells about distribution.

Most sources say that the kurtosis of a data set provides a measure of the peakedness of the distribution of the data, relative to the normal distribution. A positive kurtosis value indicates a relatively peaked distribution and a negative kurtosis value indicates a relatively flat distribution. But Dr. Peter Westfall published an article that addresses why kurtosis does not measure peakedness

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4321753/

He says that 'The kurtosis [...] is a measure of the combined weight of the tails relative to the rest of the distribution.'

EXAMPLE
SEE ALSO Skewness() function

References:

The Kurtosis function is used in the following formulas in AFL on-line library:

More information:

Updated on-line reference