How do you use Arena's Input Analyzer to fit distributions to your data?

1 What is Input Analyzer?

Input Analyzer is a feature of Arena Simulation Software that helps you to select and fit probability distributions to your input data. You can use it to analyze data from historical records, surveys, measurements, or other sources, and to generate random variates for your simulation model. Input Analyzer can handle both discrete and continuous data, and it can compare different distributions based on various criteria, such as goodness-of-fit tests, graphical plots, and summary statistics.

2 How to access Input Analyzer?

You can access Input Analyzer from the Tools menu in Arena, or by clicking on the Input Analyzer icon on the toolbar. You can also launch it as a standalone application from the Windows Start menu. When you open Input Analyzer, you will see a blank workspace where you can import or enter your data. You can also save and load your data and analysis settings as Input Analyzer files (.iad).

3 How to import or enter data?

There are several ways to import or enter data into Input Analyzer. You can use the File menu to open or paste data from Excel, text, or comma-separated files. You can also use the Data menu to generate data from a distribution, a function, or a time series. Alternatively, you can enter data manually by typing or copying them into the Data Editor window. You can edit, sort, or delete your data as needed, and you can label your data columns with descriptive names.

4 How to fit distributions?

Once you have your data in Input Analyzer, you can start fitting distributions to them. You can use the Fit menu to choose from a list of predefined distributions, such as normal, exponential, uniform, Poisson, etc. You can also use the Custom menu to define your own distribution using a formula or a table. Input Analyzer will automatically calculate the parameters and the goodness-of-fit measures for each distribution, and it will display them in the Fit Summary window. You can also view the fitted distributions graphically in the Histogram or Probability Plot windows.

5 How to compare distributions?

Input Analyzer allows you to compare different distributions based on various criteria, such as the Kolmogorov-Smirnov, Anderson-Darling, or Chi-Square tests, the mean square error, the Akaike information criterion, or the Bayesian information criterion. You can use the Compare menu to select the criteria and the distributions that you want to compare, and Input Analyzer will show you the results in the Compare Summary window. You can also view the comparison graphically in the Histogram or Probability Plot windows, where you can overlay multiple distributions on the same plot.

6 How to use distributions in Arena?

After you have fitted and compared the distributions that best suit your data, you can use them in your Arena simulation model. You can use the Output menu to export the distributions as Arena expressions, which are formulas that generate random variates from the distributions. You can also export the distributions as Arena data modules, which are files that contain the distribution definitions and parameters. You can then use these expressions or data modules in your Arena model blocks, such as Create, Process, Decide, etc., to specify the input parameters for your simulation.