Cumulative Plot
To plot a Cumulative Distribution after a Probabilistic analysis in RocPlane:
- Select Statistics > Plot Cumulative or the Plot Cumulative toolbar button.
- Select a Data Type.
- Enter a Number of Intervals. The default is 30, but any value between 1 and 500 can be entered.
- To display interval Markers on the plot, select the Attach Markers to Distribution check box.
- Click OK.
The Cumulative Distribution will be generated, and the mean, standard deviation, minimum and maximum values for the data plotted, will be listed at the bottom of the Distribution.
A Cumulative Distribution is, mathematically speaking, the integral of the normalized probability density function. Practically speaking, a point on the cumulative distribution gives us the probability that a random variable will be LESS THAN OR EQUAL TO a specified value.
Simply put, if (X, Y) is a point on the cumulative distribution S-curve, then Y = the probability that the random variable will be <= X.
The data Sampler allows the user to obtain the coordinates of points on the S-curve.
The same Data Types, which can be plotted with Plot Histogram, can also be plotted as Cumulative Distributions – see the Data Type topic for details.
Chart View Options
Several viewing options are available when generating a Cumulative plot. These options are available on the Chart menu and/or the right-click menu.