WEIBULL.DIST in Collabora Office: Separate Shape, Scale and Cumulative Probability

=WEIBULL.DIST(Number; Alpha; Beta; C)

Number is the nonnegative evaluation point. Alpha is the positive shape parameter and Beta is the positive scale parameter. The Collabora help explicitly distinguishes shape and scale; C=0 selects density and C=1 selects cumulative probability. Supply all four arguments.

For positive x, the independent cumulative definition is 1-EXP(-((x/Beta)^Alpha)). Its density is (Alpha/Beta)*(x/Beta)^(Alpha-1)*EXP(-((x/Beta)^Alpha)). Beta uses the same units as x; Alpha has no units. Beta is not a rate and is not generally the mean.

The distribution can model nonnegative durations under suitable assumptions. Naming a worksheet “reliability” does not make its parameters validated reliability estimates. The examples below use deliberately chosen parameters to explain the calculations.

Put 0, 5, 10, 15, 20 in A2:A6, interpreted as hours. Put shape 2 in F2 and scale 10 in F3. Enter =WEIBULL.DIST(A2;$F$2;$F$3;1) in B2 and fill down.

Independent cumulative targets are approximately 0, 0.221199217, 0.632120559, 0.894600775, 0.981684361. At ten hours, approximately 63.2% of the modeled duration distribution is at or below the evaluation point.

Use =WEIBULL.DIST(A2;$F$2;$F$3;0) in C2. At five, ten and fifteen hours the independent densities are approximately 0.077880078, 0.073575888 and 0.031619767 per hour. The density need not increase just because the cumulative probability does.

In D2 use =1-B2 and fill down for survival beyond each time. At ten hours the independent target is approximately 0.367879441; at twenty it is approximately 0.018315639.

The probability between five and fifteen hours is =WEIBULL.DIST(15;2;10;1)-WEIBULL.DIST(5;2;10;1), independently approximately 0.673401559. A difference of densities would not represent that probability.

Write the measurement unit and event beside the output. “At most fifteen hours” and “longer than fifteen hours” use complementary calculations; confusing the two reverses the operational meaning even when the numerical formula is valid.

When Alpha=1, the Weibull model becomes exponential with rate 1/Beta. Thus =WEIBULL.DIST(3;1;2;1) and =EXPON.DIST(3;0.5;1) both have independent target approximately 0.776869840.

Using Lambda=2 in the second formula would describe a different distribution. This comparison is a useful parameter-mapping test when importing a model from software that uses a rate parameter instead of a scale.

For any positive shape, evaluating x=Beta gives cumulative probability 1-EXP(-1), approximately 0.632120559. This is a scale checkpoint, not an assertion that the scale is the median.

For 0<p<1, the quantile is =Beta*(-LN(1-p))^(1/Alpha). With shape two, scale ten and p=0.95, the independent target is approximately 17.308183826 hours.

Put 0.95 in F5 and use =$F$3*(-LN(1-F5))^(1/$F$2) in F6. Passing the stored F6 result to WEIBULL.DIST in cumulative mode should target 0.95. Do not round the threshold before the check.

Require positive shape and scale and a nonnegative evaluation point. At zero, mathematical density behavior depends on shape: it is zero for shape greater than one, finite for shape one and singular for shape below one. The guide does not certify the application’s display or error treatment at that singular boundary.

The dedicated help does not establish every coercion rule or native error code. Investigate swapped parameters and mismatched units before changing the model. Extreme-tail accuracy and actual fitted-model suitability require separate verification.

The exact function is documented in Collabora Office 26.04 desktop help. Its source snapshot was retrieved on 2026-10-13 and hash-verified for this guide on October 15, 2026. Desktop documentation is not proof of Online or mobile support.

First introduced release and last functioning version are unknown. The available dedicated source does not establish those releases. No native Collabora or WPS run occurred. Numerical values are independent mathematical expectations, not certification of application-specific errors, numerical tolerances or all edge cases. Formulas use English names and semicolon separators.

The help identifies the namespace COM.MICROSOFT.WEIBULL.DIST and says this function is outside the cited OpenFormula 1.3 standard. This format disclosure does not prove identical behavior in another product. Keep exact dotted names when checking imported workbooks.

• Collabora Office 26.04: WEIBULL.DIST.
• Editorial testing standards.