CB.Fit

This function fits a specific probability distribution to a set of data (range of cells) and returns information about the fit.

Table 75. CB.Fit Returned Data Type

Returned Value	Returned Data Type
The goodness-of-fit statistic for the fit of the data to the selected distribution	Variant

You select the distribution to fit to your data (among the possible distributions listed in Table 76, CB.Fit Parameters) and the statistic to return.

CB.Fit must be used with CB.SetFitRange (CB.SetFitRange), as shown in the examples for this call.

Note:

You cannot fit to distributions that are not listed.

Table 76. CB.Fit Parameters

Parameter	VBA Data Type	Value	Description
Dist	Integer	See Table 77	Used to specify the distribution to use for fitting. Values are listed in Table 77.
Criterion	Integer	See Table 78	Used to specify which fitting statistics to return. Values appear in Table 78.
pValue (Optional)	Boolean	True or False	If False, returns the statistic; if True, returns the p-value. The default is False.
DistBestFit	Integer	See Table 77	If only one distribution is passed for Dist, DistBestFit returns the index of that distribution. Otherwise it returns the index of the best fitted distribution.
CriterionBestFit	Integer	See Table 78	If a specific ranking method is passed for Criterion, CriterionBestFit returns the index of this ranking method. Otherwise, it returns the index of the selected ranking method.

The following table shows Dist parameter values, used to select a distribution for fitting. You can only fit to distributions listed in this table.

Table 77. CB.Fit Dist Parameter Values — Required, Integer

Named Constant Value	Index Value	Description
cbDfaNormal	0	Fits to a normal distribution
cbDfaTriangular	1	Fits to a triangular distribution
cbDfaPoisson	2	Fits to a Poisson distribution
cbDfaBinomial	3	Fits to a binomial distribution
cbDfaLognormal	4	Fits to a lognormal distribution
cbDfaUniform	5	Fits to a uniform distribution
cbDfaExponential	6	Fits to an exponential distribution
cbDfaGeometric	7	Fits to a geometric distribution
cbDfaWeibull	8	Fits to a Weibull distribution
cbDfaBeta	9	Fits to a beta distribution
cbDfaGamma	12	Fits to a gamma distribution
cbDfaLogistic	13	Fits to a logistic distribution
cbDfaPareto	14	Fits to a Pareto distribution
cbDfaExtremeValue	15	Fits to an extreme value distribution
cbDfaNegBinomial	16	Fits to a negative binomial distribution
cbDfaHypergeometric Success	17	Fits to a hypergeometric distribution with Success parameter
cbDfaMinExtreme	18	Fits to a minimum extreme value distribution
cbDfaMaxExtreme	19	Fits to a maximum extreme value distribution
cbDfaStudentsT	20	Fits to a Student’s t distribution
cbDfaDiscreteUniform	22	Fits to a discrete uniform distribution
cbDfaBetaPert	23	Fits to a betaPERT distribution
cbDfaAutoSelectDist	50	Fits to whatever Crystal Ball chooses in the Distribution Gallery as the best type of distribution for fitting.
cbDfaAllContinuous	51	Fits the data to all continuous distributions in the Distribution Gallery (those distributions in which every value in the distribution’s range is possible).
cbDfaAllDiscrete	52	Fits the data to all discrete (non-continuous) distributions in the Distribution Gallery (except Yes-No)
cbDfaAllDistributions	53	Fits to all continuous and discrete distributions (except Yes-No)

Note:

The cbDfaExtremeValue constant is deprecated. It is included for Crystal Ball 2000.5 (5.5) compatibility and is replaced by cbDfaMinExtreme and cbDfaMaxExtreme in later versions of Crystal Ball . Beginning with version 11.1.1.0.00, the lognormal distribution has three parameters instead of two. If this call is used in a model that was created in an earlier version of Crystal Ball, the third parameter has a value of 0.

The following table shows Criterion parameter values, used to specify which fitting statistics to return.

Table 78. CB.Fit Criterion Parameter Values — Required, Integer

Named Constant Value	Index Value	Description
cbFitChiSquare	1	Returns the chi-square statistic
cbFitChiSquareP	2	Returns the chi-square statistic p-value.
cbFitKolmogorovSmirnov	3	Returns the Kolmogorov-Smirnov statistic
cbFitAndersonDarling	4	Returns the Anderson-Darling statistic
cbDfaAutoSelectRanking Method	5	Automatically selects a ranking method depending on characteristics of the data