A list of all the public Crystal ball features, which are grouped into three types:
1. Distributions
Functions that generate random values from probability distributions.
Crystal Ball Tools are programs that extend the functionality of Crystal Ball. They are ordered in two categories:
Setup Tools
Batch Fit
The Batch Fit tool lets you "automatically" fit (continuous) probability distributions to multiple data series. At Epix Analytics, we don't use this tool often because fitting distributions to data should be done carefully (e.g. often one by one) and not always be based on just one of the available Goodness of Fit Statistics.
Correlation Matrix
The Correlation Matrix lets you enter a matrix of correlations between assumptions in one step. In the section about Rand Order Correlation, you can see how to use this tool.
Tornado Chart
The Tornado Chart Tool allows you to determine the impact of each model variable (one at a time) on one specific forecast. In the section about Spider Charts and the Tornado Chart tool, you can read how to use this tool.
Analysis Tools
Bootstrap
The Bootstrap Tool of Crystal Ball is a special case of the more general Bootstrap method discussed in ModelAssist Advanced. Crystal Ball's Bootstrap tool looks at how robust your simulation forecast statistics are. For example, given that you have done 10,000 iterations, the Bootstrap Tool determines how precisely the forecast statistics have been determined, meaning by how much would those statistics change if one were to run an essentially infinite number of iterations. Therefore, the main use of the Crystal Ball's Bootstrap Tool is to determine if you have run sufficient iterations. In contrast, the Bootstrap method discussed in ModelAssist Advanced helps you quantify the uncertainty you have about input parameters in your risk analysis model that have been estimated from data .
Decision Table
The Decision Table tool allows you to run multiple simulations to test different values of one or two decision variables. Here, you can see how this tool can be used, with an example model. The model
Market growth model provides another example.
Scenario Analysis
The Scenario Analysis Tool allows you to examine which combination of assumption values gives you a certain forecast result. The tool runs a simulation after which it matches all the forecasts with their corresponding assumption values. In the resulting table, it shows all the forecast values in the range you specified (e.g. between 95% and 100% percentile) sorted, along with all the corresponding assumption (input) values. This tool can therefore be used as one of the methods to get a better understanding of an output of a simulation.
Two dimensional Simulation
The Two-Dimensional Simulation Tool in Crystal Ball lets you separate the effect of uncertainty (lack of knowledge) and variability and randomness in a forecast. For a more detailed descriptions, see here.
3. Statistics functions
Functions that report the simulation results within Excel cells. Although not always fully supported by Crystal Ball, these functions are very useful, in combination with on-screen recalculation, to monitor some aspect of the simulation. They are also useful for automatically producing reports in Excel, though this can slow down your models.
CB.GetForeStatFN(x,2) - mean
CB.GetForeStatFN(source,2) reports the mean of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,3) - median
CB.GetForeStatFN(source,3) reports the median of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,4) - mode
CB.GetForeStatFN(source,4) reports the mode of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,5) - standard deviation
CB.GetForeStatFN(source,5) reports the standard deviation of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,6) - variance
CB.GetForeStatFN(source,6) reports the Variance of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,7) - skewness
CB.GetForeStatFN(source,7) reports the Skewness of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,8) - kurtosis
CB.GetForeStatFN(source,8) reports the kurtosis of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,9) - coefficient of variability
CB.GetForeStatFN(source,9) reports the coefficient of variability of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,10) - minimum
CB.GetForeStatFN(source,10) reports the minimum of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,11) - maximum
CB.GetForeStatFN(source,11) reports the maximum of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,12) - range width
CB.GetForeStatFN(source,12) reports the range width of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForeStatFN(x,13) - standard error
CB.GetForeStatFN(source,13) reports the standard error of the values generated for the source (cell reference, cell name or output name) so far in the simulation.
CB.GetForePercentFN - percentile
CB.GetForePercentileFN(source,P) reports for which of the values generated for the source (cell reference, cell name or output name) so far in the simulation, the fraction P are lower.
CB.GetCertaintyFN - Target
CB.GetCertaintlyFN(Data source, target X value)/100 returns the cumulative probability for target value in the simulated distribution for the cell, output, or input.
CB.IterationsFN - Iteration
CB.IterationsFN() reports the current iteration of the simulation when running.