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See also:
The simulation settings window allows you to control how ModelRisk will
run a simulation. It is accessed by clicking 
on
the ModelRisk ribbon. The window has two tabs: Model
Settings, which controls the next individual simulation run; and
Application Settings
which defines the default settings for a number of ModelRisk parameters.
Model Settings tab
Simulation Setup group
Samples determines how many samples will be run for your model;
Simulations determines how many simulations will be run, each with the number of samples defined by the Samples dialog. The usual value to use is 1 but, in conjunction with the VoseSimTable and/or the VoseCurrentSim functions, you can build models that will run several different scenarios together using this feature;
Simulation names optionally allows you to give a name to each simulation for easier identification. Either enter a list of names, e.g.
or refer to a spreadsheet range which will copy the list in for you. If used, the name will appear in the Simulation # drop-down control in the Simulation Results window.
Options group
Refresh every … samples will update the Excel screen with the current simulated values every … samples. The option is switched off by default because it will slow down the simulation speed considerably, particularly if a small value (e.g. less than 1% of total samples to be run). If you wish to see numbers change on the screen (which can certainly capture people’s attention, particularly if one has imbedded graphs that change too), consider leaving this switched off for longer simulation runs and using the Update Screen control (the blue button at the bottom of the Simulation Progress control) which allows you to toggle switch screen updating on and off:
Stop on output error is a useful feature to debug your model. ModelRisk will stop simulating and show the scenario that produced the error.
Show results window at end of simulation will automatically pop up the Simulation Results window once ModelRisk has completed a simulation. This should normally be switched on, but you may want to deselect this option if, for example, you are only interested in the mean simulation result displayed by using VoseSimMean.
Seed group
Seed values are used to control how ModelRisk generates random samples for its stochastic variables. They are particularly useful if you wish to reproduce a set of simulation results.
Seed generating: Random will randomly select a different seed value. You can use this option, for example, to run multiple simulations of the same model with different seeds to see if there is any appreciable effect on the simulation results by using different random numbers;
Seed generating: Manual will use the seeds specified in the Seed Value(s) list
Seed Value(s) allows you to enter specific seed values. If you enter a list of values, the first value will be used in the first simulation run, etc. Seed values should be an integer between 0 and 4294967295 (2^32 -1)
Multiple simulation seeds has three options:
All use same seed: all simulations will use the first seed value specified in the Seed Value(s) field. If you use the same number of random variables in each simulation version of your model, this ensures that the difference is not due to random sampling
Use different seeds – First must be defined: the first simulation uses the first seed value specified in the Seed Value(s) field, and the remaining simulations will use different values. This helps evaluate whether the model results are materially affected by the random values being generated
Use different seeds – All must be defined: seed values for each simulation will use the list specified in the Seed Value(s) field. This can be useful if you wish to check the effect of using different seed values on your model, but is not commonly used.
Save and Load group
You can save simulation settings, and load previously saved settings. The simulation settings file takes a .vmro extension.
Macro Settings Tab
The Macro settings tab controls VBA macros that are run before and after simulation samples and simulation runs. The tab allows specifying 4 places at which the VBA macros can be run:
1. Before each simulation
2. Before each sample
3. After each sample
4. After each simulation
The VBA macros can be chosen from the list of available macros saved in the current workbook:
Application Settings tab
Application settings control some basic ModelRisk default actions.
General group
Show welcome screen determines whether the following screen will appear on start-up:
This screen can also be accessed at any time through the Help menu:
Save Results determines whether, when one saves a spreadsheet model for which a simulation has been performed, ModelRisk will prompt the user whether to save a simulation results file.
Simulation Settings group
Samples is the default number of samples, which appears in the ModelRisk toolbar or ribbon:
The default number of samples is easily over-ridden by typing a different number in this window, or in the Model Settings window.
Stop on output error determines the default setting, which can be over-ridden for an individual model run in the Model Settings window.
Show results window at end of simulation determines whether up the Simulation Results window will automatically pop once ModelRisk has completed a simulation. The setting can be over-ridden for an individual model run in the Model Settings window.
Simulation Results group
Histogram Bars determines how many bars there will be in a histogram plot of simulation results. The Auto option will select the number of bars to reflect the level of detail implied by the number of samples taken in a simulation run. The number of bars can still be changed for individual histogram plots in the Simulation Results window.
Histogram View determines whether the default plotting of histograms should be bars or lines. This can still be changed for individual histogram plots in the Simulation Results window.
Histogram sliders determines the default location for sliders in terms of cumulative probabilities. This can still be changed for individual histogram plots in the Simulation Results window.
Box-plot percentiles determines the default percentiles plotted around the 50th percentile for box-plots. This can still be changed for individual histogram plots in the Simulation Results window.
Trend-plot percentiles determines the default percentiles plotted around the mean for trend plots. This can still be changed for individual histogram plots in the Simulation Results window.
Library group
Allow the user to set the location of the ModelRisk Library on a local computer.
