Manuals/calci/BETADIST

Revision as of 23:53, 10 December 2013 by Abin (talk | contribs) (→‎Description)
BETADIST(x,alpha,beta,a,b)


  • x is the value between a and b,
  • alpha and beta are the value of the shape parameter
  • a & b the lower and upper limit to the interval of x.

Description

  • This function gives the Cumulative Beta Probability Density function.
  • The beta distribution is a family of Continuous Probability Distributions defined on the interval [0, 1] parameterized by two positive shape parameters, denoted by   and  .
  • The Beta Distribution is also known as the Beta Distribution of the first kind.
  • In  ,   is the value between   and  .
  • alpha is the value of the shape parameter.
  • beta is the value of the shape parameter
  •   and  (optional) are the Lower and Upper limit to the interval of  .
  • Normally   lies between the limit   and  , suppose when we are omitting   and   value, by default   value with in 0 and 1.
  • The Probability Density Function of the beta distribution is:

  where  ;   and   is the Beta function.

  • The formula for the Cumulative Beta Distribution is called the Incomplete Beta function ratio and it is denoted by   and is defined as :

Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle F(x)=I_x(\alpha,\beta)=\int_{0}^{x}\frac{t^{α−1}(1−t)^{\beta−1}dt} {B(\alpha,\beta)}} , where  0 ;   and   is the Beta function.

  • This function will give the result as error when
1.Any one of the arguments are non-numeric
2.  or  
3.  , , or a=b
  • we are not mentioning the limit values   and  ,

by default it will consider the Standard Cumulative Beta Distribution, a = 0 and b = 1.

Examples

  1. =BETADIST(0.4,8,10) = 0.359492343
  2. =BETADIST(3,5,9,2,6) = 0.20603810250
  3. =BETADIST(9,4,2,8,11) = 0.04526748971
  4. =BETADIST(5,-1,-2,4,7) = NAN

See Also

References

Beta Distribution