STOPCRITERIA subcommand (SIMPLAN command)

The STOPCRITERIA subcommand specifies criteria for stopping the simulation, potentially before the maximum number of allowable cases has been generated.

MAXCASES. Specifies the maximum number of cases of simulated data to generate. The default is 100000. A larger value for MAXCASES will allow for more accurate predictions but will also require a longer execution time to complete the simulation.
  • When the TARGET and TYPE keywords are omitted, this is the number of cases that will be generated.
  • When sensitivity analysis is specified, this is the maximum number of cases for each iteration.
  • When the MODEL subcommand is omitted, MAXCASES is the only option.

TARGET. The name of the target to which the criteria specified on the TYPE keyword are applied.

TYPE Keyword

The TYPE keyword specifies the criteria for stopping the simulation. The TYPE keyword is ignored if the TARGET keyword is omitted.

MEAN. Specifies to continue generating cases until the confidence interval of the mean of the target distribution is within a specified threshold. To use this option, you specify a confidence level and a threshold. For example, you can use this option to specify that cases are generated until the confidence interval of the mean at the 95% confidence level is within 5% of the mean value.

  • The keyword THRESH specifies the threshold value for the confidence interval at the confidence level specified by the CILEVEL keyword. The default for CILEVEL is 95, representing a confidence level of 95%.
  • The keyword UNIT indicates whether the value specified for THRESH represents a percentage of the mean value of the target (UNIT=PERCENT) or a numeric value (UNIT=VALUE). For example, if your target is revenue and you want to ensure that the width of the 95% confidence interval of the mean is less than $1000 then you would specify THRESH=1000 UNIT=VALUE. When UNIT=PERCENT, THRESH is specified as an integer, as in the value 5 for 5%.
  • Generation of cases will continue until the criteria specified in MEAN is reached or the maximum number of allowed cases (MAXCASES keyword) has been reached

TAIL. Specifies to continue generating cases until a given number of cases have been generated in one of the tails of the distribution for the specified target.

  • For UNIT=VALUE, the THRESH keyword specifies the value of the target that defines the boundary of the tail region. By default, the value is assumed to specify the right tail region. To specify the left tail region, use SIDE=LEFT.
  • For UNIT=PERCENTILE, the THRESH keyword specifies the boundary of the tail region as a percentile of the target distribution. The SIDE keyword is ignored when UNIT=PERCENTILE, since the side is implicit in the specified value of THRESH--for example, a value of 99 implies the right tail and a value of 1 implies the left tail.
  • The FREQUENCY keyword specifies the number of cases that must be generated in the specified tail region.
  • Generation of cases will continue until the criteria specified in TAILS is reached or the maximum number of allowed cases (MAXCASES keyword) has been reached

Examples

This example specifies that exactly 1,000,000 cases of simulated data will be generated.

/STOPCRITERIA MAXCASES=1000000

This example specifies that cases will be generated until either the width of the 99% confidence interval of the mean of the target profit is within 1% of the mean value, or 1,000,000 cases have been generated.

/STOPCRITERIA MAXCASES=1000000
 TARGET=profit
 TYPE=MEAN(THRESH=1 UNIT=PERCENT CILEVEL=99)

This example specifies that the boundary of the right tail region for the target loss is at the value 50,000,000. Cases will be generated until either 500 cases have a target value greater than 50,000,000 or 10,000,000 cases have been generated.

/STOPCRITERIA MAXCASES=10000000
 TARGET=loss
 TAIL(UNIT=VALUE THRESH=50000000 FREQUENCY=500)