Chart Options

In the Chart Options dialog box you can customize the display of activated charts of probability density functions and cumulative distribution functions that are generated from a simulation.

View. The View drop-down list only applies to the probability density function chart. You can use it to toggle the chart view from a continuous curve to a histogram. This feature is disabled when multiple density functions (from multiple iterations) are displayed on the same chart. When there are multiple density functions, the density functions can only be viewed as continuous curves.

Order. The Order drop-down list only applies to the cumulative distribution function chart. It specifies whether the cumulative distribution function is displayed as an ascending function (the default) or a descending function. When displayed as a descending function, the value of the function at a given point on the horizontal axis is the probability that the target field lies to the right of that point.

Slider positions. The Upper text field contains the current position of the right sliding reference line. The Lower text field contains the current position of the left sliding reference line. You can explicitly set the positions of the sliders by entering values in the Upper and Lower text fields. The value in the Lower text field must be strictly less than the value in the Upper text field. You can remove the left reference line by selecting -Infinity, effectively setting the position to negative infinity. This action disables the Lower text field. You can remove the right reference line by selecting Infinity, effectively setting its position to infinity. This action disables the Upper text field. You cannot remove both reference lines; selecting -Infinity disables the Infinity check box, and vice versa.

Reference lines. You can add various fixed vertical reference lines to probability density functions and cumulative distribution functions.

  • Mean. You can add a reference line at the mean of the target field.
  • Median. You can add a reference line at the median of the target field.
  • Standard Deviations. You can add reference lines at plus and minus a specified number of standard deviations from the mean of the target field. You can enter the number of standard deviations to be used in the adjoining text field. The minimum number of standard deviations is 1, and the maximum is 10. The number of standard deviations is initially set to 3.
  • Percentiles. You can add reference lines at one or two percentile values of the distribution for the target field by entering values into the Bottom and Top text fields. For example, a value of 95 in the Top text field represents the 95th percentile, which is the value below which 95% of the observations fall. Likewise, a value of 5 in the Bottom text field represents the fifth percentile, which is the value below which 5% of the observations fall. For the Bottom text field, the minimum percentile value is 0, and the maximum is 49. For the Top text field, the minimum percentile value is 50, and the maximum is 100.
  • Custom positions. You can add reference lines at specified values along the horizontal axis. You can remove custom reference lines by deleting the entry from the grid.

When you click OK, the sliders, labels above the sliders, reference lines, and the table below the chart are updated to reflect the options that are selected in the Chart Options dialog box. Click Cancel to close the dialog box without making any changes. Reference lines can be removed by deselecting the associated choice in the Chart Options dialog and clicking OK.

Note: When multiple density functions or distribution functions are displayed on a single chart (because of results from sensitivity analysis iterations), reference lines (other than custom lines) are separately applied to each function. Only the reference lines for the first iteration are shown. The reference line labels include the iteration label. The iteration label is derived from upstream, typically from a Simulation Generate node. If no iteration label is available, the iteration value is used instead. The Mean, Median, Standard Deviations, and Percentiles options are disabled for cumulative distribution functions with multiple iterations.