WEIBULL ( x , alpha , beta , cumulative-flag )
Description: Computes the Weibull distribution.
Mathematical Formula:
The equation for the Weibull cumulative distribution function is:
The equation for the Weibull probability density function is:
When alpha = 1, WEIBULL returns the exponential distribution with:
Arguments:
|
Name |
Type |
Description |
|
number |
The value at which the distribution is to be evaluated. | |
|
alpha |
number |
A parameter of the distribution. |
|
beta |
number |
A parameter of the distribution. |
|
cumulative-flag |
logical |
Determines the form of the function. If TRUE, GAMMADIST returns the cumulative distribution function; if FALSE, it returns the probability density function. |
Return Type and Value: number – The Weibull distribution.
However, if
• x < 0, #NUM! is returned.
• alpha ≤ 0, #NUM! is returned.
• beta ≤ 0, #NUM! is returned.
[Example:
WEIBULL(105,20,100,TRUE) results in 0.92958139
WEIBULL(105,20,100,FALSE) results in 0.035588864
end example]