Omit Some Periods at the Start

This allows you to omit some periods (that is, simulations) at the start of the Closure/Shocks page and to replace the First Year Data files by those produced by the Base simulation for the last of the years omitted. This action is available either under the File menu, or via a button on the Sim Overview page.

For example, you may have an application in which you think of the first 4 periods (each covering one year) of the Base as reproducing history. Once you have run these 4 simulations of the Base case, you may prefer to think of everything else (the remaining periods of the Base and all periods of the Policy) as starting from the data files produced at the end of year 4 of the Base. In this case you would want to specify those data files as the First Year Data files (on the Model/Data page) and would want to remove these 4 periods (simulations) from the Closure/Shocks page. If so, this Omit Some Periods at the Start procedure is ideal.

When you begin this procedure, you are asked how many periods to omit at the start.

You are also asked if you want to change the files in the First Year Data part of the Model/Data page to reflect this.

Suppose for example that you begin from 1997 data, that all periods cover one year, and that you have 4 years of history which bring you to Base data files for the year 2001. Suppose that there are simulations for 12 years on the Sim Overview page. Then, if you ask to omit these 4 periods at the start and ask to have the First Year Data part of the Model/Data page changed accordingly,

•The Sim Overview page will change to show the starting data as data for 2001, and will now show simulations for just 8 years.

•The first 4 years (rows) will be deleted from the Closure/Shocks page, which will now show Closure and Shocks files for the 8 years 2002 to 2009.

•The First Year Data part of the Model/Data page will list the files from the simulation for the year 2001 of the Base.

If you ask to have the First Year Data files changed accordingly and any one of the files does not exist (or if, according to RunDynam) you have not yet run the Base simulation for that year, you will be asked if you want to continue.

Thanks to Glyn Wittwer for suggesting this feature.

URL of this topic: www.copsmodels.com/webhelp/rundynam/hc_omityearsstart.htm

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