Leading the way in Microsoft Office Development
 Home|Excel|Word|PowerPoint|Consultancy|Feedback|Contact 
 Microsoft Excel > Functions > Statistical > GAMMAINV
 

GAMMAINV(probability, alpha, beta)

 
 Returns the inverse of the gamma distribution.

 probabilityThe probability associated with the gamma distribution.
 alphaThe first parameter to the distribution.
 betaThe second parameter to the distribution.

 REMARKS
 
  		• The inverse of the gamma distribution is the inverse of the GAMMADIST() function.
     
  		• If any of the arguments are not numeric, then #VALUE! is returned.
     
  		• If "probability" < 0, then #NUM! is returned.
     
  		• If "probability" > 1, then #NUM! is returned.
     
  		• If "alpha" = 0, then #NUM! is returned.
     
  		• If "beta" = 0, then #NUM! is returned.
     
  		• If "beta" = 1, then the standard gamma distribution is used ??
     
  		• If "beta" = 0, then #NUM! is returned.
     
  		• GAMMAINV uses an iterative technique for calculating the function. Given a probability value, GAMMAINV iterates until the result is accurate to within ±3x10^-7.
     
  		• If this function does not converge after 100 iterations, then #N/A is returned.
     
  		• The accuracy of this function was improved in Excel 2003. For more information please refer to this Knowledge Base Article (828334).

     EXAMPLES
     
     A
    1=GAMMAINV(0.068094,9,2) = 10
    2=GAMMAINV(0.5,4,2) = 7
    3=GAMMAINV(0.068,4,2) = 3
    4=GAMMAINV(GAMMADIST(7,5,1,TRUE),5,1) = 7
    5=GAMMAINV(0.5,4,2) = 7
    6=GAMMAINV(0.5,-9,2) = #NUM!
    7=GAMMAINV(-2,9,2) = #NUM!
    8=GAMMAINV(-2,"some text",2) = #VALUE!
    		 
     Functions - G | Index - G | Office Online 

     Copyright © 2004-2007 Better Solutions Limited. All Rights Reserved.Top