Convergence Plot: Probabilistic Analysis

The Convergence Plot option in the Statistics menu, allows you to view the progress of a Probabilistic Analysis, to determine whether or not the analysis results are converging to constant values, and the approximate number of samples at which convergence occurs. This can help to determine:

To create a Convergence Plot:

  1. Select Convergence Plot from the toolbar or the Statistics menu.

  2. In the Convergence Plot dialog:

  1. Select the Plot button to generate the plot.

  2. Once a plot is generated, there are several options available, if you right-click the mouse on the plot. See below for details.

Convergence Plot

The following analysis results can be plotted on a Convergence Plot:

The mean and standard deviation plots (Factor of Safety, or Probability of Failure), are obtained by recalculating the mean and standard deviation of the results, after EACH sample iteration of the Probabilistic Analysis.

The minimum Factor of Safety plot, simply keeps track of the minimum safety factor which has been computed. This plot will always decrease monotonically, with increasing number of samples.

All of these plots should eventually converge to constant values, as the Number of Samples increases.

Right Click Options

Several options are available if you right-click on a Convergence Plot. For example:

Experiment with the different options available in the right-click menu.