Manuals/calci/FDIST

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FDIST(x,df1,df2)


  • is the value of the function
  • and is degrees of freedom.

Description

  • This function gives the value of F probability distribution.
  • This distribution is continuous probability distribution and it is called Fisher-Snedecor distribution.
  • The F distribution is an asymmetric distribution that has a minimum value of 0, but no maximum value.
  • In   is the value of the function ,  is the numerator degrees of freedom and   is the denominator degrees of freedom.
  • This distribution is the ratio of two chi-square distributions with degrees of freedom r1 and r2, respectively, where each chi-square has first been divided by its degrees of freedom.
  • The Probability density function of the F distribution is:

    where   is the Gamma Function.

  • The gamma function is defined by <math>\Gamma(t) = \int\limits_{0}^{infty} x^{t-1} e^{-x} dx/math>.

When the value of df1 and df2 are not integers ,then it is converted in to integers.

  • This function will give the result as error when
 1. any one of the argument is nonnumeric.
 2.x is negative
 3. df1 or df2<1 ,and  df1 ordf2>=10^10

Examples

  1. FDIST(20.6587,7,3)=0.01526530981
  2. FDIST(70.120045,12.2,6.35)=0.000011229898
  3. FDIST(10,1.3,1.5)=0.134947329626
  4. FDIST(-28,4,6)=NAN


See Also


References