Histogram Plot

To generate a Histogram Plot of any quantitative data column in Grid Data:

1. Select Statistics > Plot Histogram.
2. In the Histogram Plot Parameters dialog:
   1. Select a Data Type from the drop-down list. Any quantitative Grid Data column can be plotted.
      NOTE: Qualitative data will not be interpreted correctly as numeric data.
   2. Enter a Number of Intervals. The default is 30, but any value between 1 and 500 can be entered.
   3. Select the Best Fit Distribution check box to determine the Best Fit Distribution for the variable using the Kolmogorov-Smirnov Goodness of Fit test.
   4. Select the Attach Markers to Distribution check box to display interval Markers on the plot.
   5. Select OK to plot the histogram.

The Histogram is generated, and the mean, standard deviation, minimum and maximum values for the data plotted are listed at the bottom of the Histogram.

Right-Click Options

Several viewing options are available when generating a Histogram plot. These options are available on the Chart menu and/or the right-click menu.

• Relative Frequency
• Best Fit Distribution
• Sampler
• 3D Histogram
• Chart Properties
• Custom Histogram Options
• Copy Chart/Data to Clipboard
• Copy Picture to Clipboard
• Plot in Excel

Relative Frequency

The Relative Frequency option allows you to scale the Frequency axis of Histograms in terms of Relative Frequency.

• When the Relative Frequency option is toggled ON, the Frequency axis of a Histogram will be scaled such that the AREA under the distribution is equal to one.
• If Relative Frequency is OFF, then the Frequency axis will be in terms of the actual number of samples.

Best Fit Distribution

The Best Fit Distribution option allows you to determine the best fit distribution for the plotted data and can be displayed on the histogram along with the distribution parameters (mean, standard deviation and min, max values).

The Best Fit Distribution option is available in the right-click menu, and the Chart menu.

3D Histogram

The 3D Histogram option changes the style of the histogram to display 3D bars.

Custom Histogram Options

The Custom Histogram Options allows the user to set:

• Custom Histogram Range: Set the Min and Max range of the histogram.
• Best Fit Distribution Filter: Select the distributions (e.g., Normal , Uniform, Triangular, Beta, Exponential, Lognormal, Gamma) to use for generating the Best Fit Distribution. By default, all distributions are considered.

Sampler

The Sampler option on a Histogram Plot allows you to easily determine the coordinates at any point along the histogram values.

1. Right-click on the Histogram Plot, and select the Sampler > Show Sampler option.
2. You will see a dotted cross-hair line on the plot. This is the “Sampler”, and allows you to graphically obtain the coordinates of any point on the histogram.
3. As you move the mouse over the histogram data, you will see that the Sampler follows the mouse, and continuously displays the coordinates of points on the histogram plot.