Manuals/calci/WEIBULL

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WEIBULL(x,alpha,beta,lv)


  • is the value of the function.
  • and are the parameter of the distribution.
  • is the logical value.

Description

  • This function gives the value of the weibull distribution with 2-parameters.
  • It is a continuous probability distribution.
  • Weibull distribution also called Rosin Rammler distribution.
  • It is used to model the lifetime of technical devices and is used to describe the particle size distribution of particles generated by grinding, milling and crushing operations.
  • This distribution is closely related to the lognormal distribution.
  • In , is the value to evaluate the function.
  • is the shape parameter of the distribution. is the scale parameter of the distribution.
  • is the logical value which determines the form of the distribution.
  • When is TRUE, this function gives the value of the cumulative distribution. When is FALSE, then this function gives the value of the probability density function.
  • When we are not omitting the value of , then it consider as FALSE.
  • Weibull distribution is of two type :3-parameter weibull distribution and 2-parameter weibull distribution.
  • This function gives the value of 2-parameter weibull distribution by setting the third parameter (location parameter) is zero.
  • Also if alpha<1,then the failure rate of the device decreases over time.
  • If alpha=1, then the failure rate of the device is constant over time.
  • If alpha>1, then the failure rate of the device increases over time.
  • The equation for cumulative distribution function is: Failed to parse (syntax error): {\displaystyle F(x,\alpha,\beta) = 1-e^-{(\frac{x}{β})}^α}
  • The equation for probability density function is:

  • When alpha =1, then this function gives the exponentail with .
  • This function gives the result as error when
   1. Any one of the argument is non-numeric.
   2. x is negative.
   3.alpha or beta <math>\le 0.

WEIBULL(x,alpha,beta,lv), where , and , and .

WEIBULL(x ,a, b, cum)

Where 'x' Is the value at which to estimate the function, 'a'(Alpha) and 'b'(Beta) are the parameters to the distribution, and 'cum' determines the form of the function.


  This function returns the Weibull distribution.

 
  • WEIBULL returns the error value, when x, a, b is nonnumeric or x < 0
  • WEIBULL returns the error value, when a ≤ 0 or b ≤ 0.
  • 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:

WEIBULL


Lets see an example,

B

100

25

110

?UNIQ686c29c343f4309c-nowiki-00000004-QINU?

?UNIQ686c29c343f4309c-nowiki-00000005-QINU?


Syntax

Remarks

Examples

Description

Column1 Column2 Column3 Column4
Row1 100 0.088165
Row2 25 0.02104
Row3 110
Row4
Row5
Row6