Integer Uniform(min,max):
= DiscreteUniform(min,max), which is a special case of the more general Discrete Uniform distribution that one can construct with Crystal Ball's Custom Distribution
The Integer Uniform distribution is a distribution used to describe a variable that can take one of several consecutive explicit integer values. For example, the resulting value from throwing a die 1 time. An example of the Integer Uniform distribution is shown below:
Uses
It is not often that we come across a variable that can take one of several equally-spaced values each with equal probability. However, there are a couple of modeling techniques that require that capability:
Bootstrap
Resampling in univariate non-parametric Bootstrap
Fitting empirical distribution to data
Creating an empirical distribution directly from a data set, i.e. where we believe that the list of data values is a good representation of the randomness of the variable.
Bayesian analysis by simulation
An Integer Uniform distribution can represent an uninformed prior for a discrete variable, so it is useful when you perform a Bayesian inference analysis with simulation using accept/reject criteria. The pats model is an example.
Generation
The Integer Uniform distribution is not directly available in Crystal Ball 5.5- as a distribution but can be readily created using Crystal Ball's Uniform distribution and Excel's ROUND function as follows:
A1 = 1 (min)
A2 = 5 (max)
B1 = A1 - 0.5
B2 = A2 + 0.5
A3 = Uniform(B1,B2)
A4 = ROUND(A3, 0)
In Crystal Ball 7.0+, you can use the DiscreteUniform Distribution available in the distribution gallery.
