Difference between revisions of "Manuals/calci/KURT"

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*Kurtosis is defined by:
 
*Kurtosis is defined by:
 
*Kurtosis=:
 
*Kurtosis=:
<math>\frac{n(n+1)}{(n-1)(n-2)(n-3)} \frac{\sum (xi-\bar{x})^4}{s}- \frac{3(n-1)^2}{(n-2)(n-3)}</math>, where <math>s</math> is the Sample Standard Deviation.<math>\bar{x}</math> is the Arithmetic Mean.
+
<math>\frac{n(n+1)}{(n-1)(n-2)(n-3)} \frac{\sum (x_{i}-\bar{x})^4}{s}- \frac{3(n-1)^2}{(n-2)(n-3)}</math>, where <math>s</math> is the Sample Standard Deviation.<math>\bar{x}</math> is the Arithmetic Mean.
 
*In this function arguments may be any type like numbers,names,arrays or references that contain numbers.
 
*In this function arguments may be any type like numbers,names,arrays or references that contain numbers.
 
*We can give logical values and text references also directly.
 
*We can give logical values and text references also directly.

Revision as of 23:50, 18 December 2013

KURT(n1,n2,…)


  • , are values to calculate kurtosis.

Description

  • This function gives the value of Kurtosis of a given set.
  • Kurtosis is the peak or flatness of a frequency distribution graph especially with respect to the concentration of values near the Mean as compared with the Normal Distribution.
  • A normal distribution has a Kurtosis of 3.
  • Distributions having higher Kurtosis have flatter tails or more extreme values that phenomenon called 'leptokurtosis' also it is the positive excess Kurtosis , and those with lower Kurtosis have fatter middles or fewer extreme value that phenomenon called 'Platykurtosis' also it is the negative excess Kurtosis.
  • Example for positive Kurtosis(leptokurtosis) is Exponential distribution, Poisson distribution, Laplace Distribution.
  • Example for Negative Kurtosis(platykurtosis) is Bernoulli distribution, Uniform distribution.
  • Kurtosis has no units.
  • Kurtosis is defined by:
  • Kurtosis=:

, where is the Sample Standard Deviation. is the Arithmetic Mean.

  • In this function arguments may be any type like numbers,names,arrays or references that contain numbers.
  • We can give logical values and text references also directly.
  • Suppose the referred argument contains any null cells, logical values like that values are not considered.
  • This function will return the result as error when
1.Any one of the argument is non-numeric.
2.Suppose the number of data points are less than four or the standard deviation of the sample is zero
3.The referred arguments could not convert
  in to numbers.

Examples

Spreadsheet
A B C D E
1 14 11 23 54 38
2 6 7 8 9 10
3 1898 1987 1786 1947
4 26 16 12
5
  1. =KURT(A1:E1) = 0.870901113729
  2. =KURT(A2:E2) = -1.199999999
  3. =KURT(A3:D3) = 0.870901113729
  4. =KURT(A4:C4) = NAN

See Also

References

Kurtosis