BETA.DIST

BETA.DIST(x, alpha, beta, cumulative [,A] [,B])

Returns the probability distribution function OR the cumulative probability function for a beta distribution.

x	The number between A and B from the distribution.
alpha	The first parameter.
beta	The second parameter.
cumulative	A logical value indicating the type of function to use: False (or 0) = individual probability (equal to) True (<> 0) = cumulative probability (equal to or less than)
A	(Optional) The lower bound to the interval of x (0..1) (0)
B	(Optional) The upper bound to the interval of x (0..1) (1)

REMARKS

* For an illustrated example refer to the page under Distributions
* The beta distribution is a continuous distribution
* This function is a two variable function.
* If "alpha" = "beta", the distribution is symmetrical.
* If "alpha" = 1 and "beta" > 1, the distribution is J-shaped.
* If "alpha" > 1 and "beta" = 1, the distribution is J-shaped.
* If "alpha" < "beta", the distribution is said to be positively skewed (most of the values are near the minimum value).
* If "alpha" > "beta", the distribution is negatively skewed (most of the values are near the maximum value).
* If "cumulative" = False, then the height of the curve at "x" is returned.
* If "cumulative" = True, then the area under the curve to the left of "x" is returned.
* If "A" is left blank, then 0 is used.
* If "B" is left blank, then 1 is used.
* You can use the BETA.INV function to return the inverse of the cumulative probability function for a beta distribution.
* You can use the GAMMA.DIST function to return the probability function OR the cumulative probability function for a gamma distribution.
* This function was added in Excel 2010 to replace the BETADIST function and include an option for probability distribution.
* For the Microsoft documentation refer to support.microsoft.com
* For the Google documentation refer to support.google.com

	A
1	=BETA.DIST(2, 8, 10, TRUE, 1, 3) = 0.685
2	=BETA.DIST(-2, 8, 10, TRUE, -5, 3) = 0.282
3	=BETA.DIST(3, 1, 1, TRUE, 2, 3) = 1
4	=BETA.DIST(3, 1, 1, TRUE, , 3) = 1
5	=BETA.DIST(3, -1, 1, TRUE, 2, 2) = #NUM!
6	=BETA.DIST(3, 1, 1, TRUE, 2, ) = #NUM!
7	=BETA.DIST(3, 1, -1, TRUE, 2, 2) = #NUM!
8	=BETA.DIST(3, 1, 1, TRUE, 2, 2) = #NUM!
9	=BETA.DIST(3, 1, 1, TRUE, 2, "some text") = #VALUE!