Simulation and Modelling - Old Questions

9. What do you understand by replication of runs. Why is it necessary?

Replication of run is used to obtain independent results by repeating the simulation. Repeating the experiment with different random numbers for the same sample size n gives a set of independent determinations of the sample mean  .The mean of the means and the mean of the variances are then used to estimate the confidence interval.

Suppose the experiment is repeated p times with independent random values of n sample sizes. Let x_ij be the i^th observation in j^th run and let the sample mean and the variance for the j^th run is denoted by  and  respectively. Then for j^th run, the estimates are

Combining the result of p independent measurement gives the following estimate for the mean and variance s² of the populations as:

Replication of runs are necessary for running experiments based on scenarios with stochastic parameters. It is used to obtain independent results by repeating the simulation. If replications are not used, a single run of an experiment will not produce statistically significant results and will not allow for proper calculation of statistical data.