The Distribution Report

Follow the instructions in Example of the Distribution Platform to produce the report shown in The Initial Distribution Report Window.

The Initial Distribution Report Window

Note: Any rows that are excluded in the data table are also hidden in the histogram.

The initial Distribution report contains a histogram and reports for each variable. Note the following:

•	To replace a variable in a report, from the Columns panel of the associated data table, drag and drop the variable into the axis of the histogram.

•	To insert a new variable into a report, creating a new histogram, drag and drop the variable outside of an existing histogram. The new variable can be placed before, between, or after the existing histograms.

Note: To remove a variable, select Remove from the red triangle menu.

•	The red triangle menu next to Distributions contains options that affect all of the variables. See Distribution Platform Options.

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The red triangle menu next to each variable contains options that affect only that variable. See Options for Categorical Variables or Options for Continuous Variables. If you hold down the Control key and select a variable option, the option applies to all of the variables that have the same modeling type.

•	Histograms visually display your data. See Histograms.

•	The initial report for a categorical variable contains a Frequencies report. See The Frequencies Report.

•	The initial report for a continuous variable contains a Quantiles and a Summary Statistics report. See The Quantiles Report and The Summary Statistics Report.

Histograms

Histograms visually display your data. For categorical (nominal or ordinal) variables, the histogram shows a bar for each level of the ordinal or nominal variable. For continuous variables, the histogram shows a bar for grouped values of the continuous variable.

Histogram Actions
Highlighting data	Click on a histogram bar or an outlying point in the graph. The corresponding rows are highlighted in the data table, and corresponding sections of other histograms are also highlighted, if applicable. See Highlight Bars and Select Rows.
Creating a subset	Double-click on a histogram bar, or right-click on a histogram bar and select Subset. A new data table is created that contains only the selected data.
Resizing the entire histogram	Hover over the histogram borders until you see a double-sided arrow. Then click and drag the borders. For more details, see the Using JMP book.
Rescaling the axis	(Continuous variables only) Click and drag on an axis to rescale it. Alternatively, hover over the axis until you see a hand. Then, double-click on the axis and set the parameters in the Axis Specification window.
Resizing histogram bars	(Continuous variables only) There are multiple options to resize histogram bars. See Resize Histogram Bars for Continuous Variables.
Specifying your selection	Specify the data that you select in multiple histograms. See Specify Your Selection in Multiple Histograms.

To see additional options for the histogram or the associated data table:

•	Right-click on a histogram. See the Using JMP book.

•	Right-click on an axis. You can add a label or modify the axis. See the Using JMP book.

•	Click on the red triangle next to the variable, and select Histogram Options. Options are slightly different depending on the variable modeling type. See Options for Categorical Variables or Options for Continuous Variables.

Resize Histogram Bars for Continuous Variables

Resize histogram bars for continuous variables by using the following:

•	the Grabber (hand) tool

•	the Set Bin Width option

•	the Increment option

Use the Grabber Tool

The Grabber tool is a quick way to explore your data.

1.	Select Tools > Grabber.

Note: (Windows only) To see the menu bar, you might need to hover over the bar below the window title. You can also change this setting in File > Preferences > Windows Specific.

2.	Place the grabber tool anywhere in the histogram.

3.	Click and drag the histogram bars.

Think of each bar as a bin that holds a number of observations:

•	Moving the hand to the left increases the bin width and combines intervals. The number of bars decreases as the bar size increases.

•	Moving the hand to the right decreases the bin width, producing more bars.

•	Moving the hand up or down shifts the bin locations on the axis, which changes the contents and size of each bin.

Use the Set Bin Width Option

The Set Bin Width option is a more precise way to set the width for all bars in a histogram. To use the Set Bin Width option, from the red triangle menu for the variable, select Histogram Options > Set Bin Width. Change the bin width value.

Use the Increment Option

The Increment option is another precise way to set the bar width. To use the Increment option, double-click on the axis, and change the Increment value.

Highlight Bars and Select Rows

Clicking on a histogram bar highlights the bar and selects the corresponding rows in the data table. The appropriate portions of all other graphical displays also highlight the selection. Highlighting Bars and Rows shows the results of highlighting a bar in the height histogram. The corresponding rows are selected in the data table.

Tip: To deselect specific histogram bars, press the Control key and click the highlighted bars.

Highlighting Bars and Rows

Specify Your Selection in Multiple Histograms

Extend or narrow your selection in histograms as follows:

•	To extend your selection, hold down the Shift key and select another bar. This is the equivalent of using an or operator.

•	To narrow your selection, hold down the Control and Alt keys (Windows) or Command and Alt keys (Macintosh) and select another bar. This is the equivalent of using an and operator.

Related Information

•	Example of Selecting Data in Multiple Histograms

The Frequencies Report

For nominal and ordinal variables, the Frequencies report lists the levels of the variables, along with the associated frequency of occurrence and probabilities.

For each level of a categorical (nominal or ordinal) variable, the Frequencies report contains the information described in Description of the Frequencies Report. Missing values are omitted from the analysis.

Tip: Click a value in the Frequencies report to select the corresponding data in the histogram and data table.

Description of the Frequencies Report
Level	Lists each value found for a response variable.
Count	Lists the number of rows found for each level of a response variable. If you use a Freq variable, the Count is the sum of the Freq variables for each level of the response variable.
Prob	Lists the probability (or proportion) of occurrence for each level of a response variable. The probability is computed as the count divided by the total frequency of the variable, shown at the bottom of the table.
StdErr Prob	Lists the standard error of the probabilities. This column might be hidden. To show the column, right-click in the table and select Columns > StdErr Prob.
Cum Prob	Contains the cumulative sum of the column of probabilities. This column might be hidden. To show the column, right-click in the table and select Columns > Cum Prob.

The Quantiles Report

For continuous variables, the Quantiles report lists the values of selected quantiles (sometimes called percentiles).

Related Information

•	Statistical Details for Quantiles

The Summary Statistics Report

For continuous variables, the Summary Statistics report displays the mean, standard deviation, and other summary statistics. You can control which statistics appear in this report by selecting Customize Summary Statistics from the red triangle menu next to Summary Statistics.

Tip: To specify which summary statistics show in the report each time you run a Distribution analysis for a continuous variable, select File > Preferences > Platforms > Distribution Summary Statistics, and select the ones you want to appear.

•	Description of the Summary Statistics Report describes the statistics that appear by default.

•	Additional Summary Statistics describes additional statistics that you can add to the report using the Customize Summary Statistics window.

Description of the Summary Statistics Report

Mean

Estimates the expected value of the underlying distribution for the response variable, which is the arithmetic average of the column’s values. It is the sum of the non-missing values divided by the number of non-missing values.

Std Dev

The normal distribution is mainly defined by the mean and standard deviation. These parameters provide an easy way to summarize data as the sample becomes large:

•	68% of the values are within one standard deviation of the mean

•	95% of the values are within two standard deviations of the mean

•	99.7% of the values are within three standard deviations of the mean

Std Err Mean

The standard error of the mean, which estimates the standard deviation of the distribution of the mean.

Upper 95% Mean and Lower 95% Mean

Are 95% confidence limits about the mean. They define an interval that is very likely to contain the true population mean.

Is the total number of nonmissing values.

Additional Summary Statistics
Sum Weight	The sum of a column assigned to the role of Weight (in the launch window). Sum Wgt is used in the denominator for computations of the mean instead of N.
Sum	The sum of the response values.
Variance	The sample variance, and the square of the sample standard deviation.
Skewness	Measures sidedness or symmetry.
Kurtosis	Measures peakedness or heaviness of tails.
CV	The percent coefficient of variation. It is computed as the standard deviation divided by the mean and multiplied by 100. The coefficient of variation can be used to assess relative variation, for example when comparing the variation in data measured in different units or with different magnitudes.
N Missing	The number of missing observations.
N Zero	The number of zero values.
N Unique	The number of unique values.
Uncorrected SS	The uncorrected sum of squares or sum of values squared.
Corrected SS	The corrected sum of squares or sum of squares of deviations from the mean.
Autocorrelation	(Appears only if you have not specified a Frequency variable.) First autocorrelation that tests if the residuals are correlated across the rows. This test helps detect non-randomness in the data.
Minimum	Represents the 0 percentile of the data.
Maximum	Represents the 100 percentile of the data.
Median	Represents the 50th percentile of the data.
Mode	The value that occurs most often in the data. If there are multiple modes, the smallest mode appears.
Trimmed Mean	The mean calculated after removing the smallest p% and the largest p% of the data. The value of p is entered in the Enter trimmed mean percent text box at the bottom of the window. The Trimmed Mean option is not available if you have specified a Weight variable.
Geometric Mean	The nth root of the product of the data.
Range	The difference between the maximum and minimum of the data.
Interquartile Range	The difference between the 3rd and 1st quartiles.
Median Absolute Deviation	(Does not appear if you have specified a Weight variable.) The median of the absolute deviations from the median.
Robust Mean	The robust mean, calculated in a way that is resistant to outliers, using Huber's M-estimation. See Huber and Ronchetti (2009).
Robust Std Dev	The robust standard deviation, calculated in a way that is resistant to outliers, using Huber's M-estimation. See Huber and Ronchetti (2009).
Enter (1-alpha) for mean confidence interval	Specify the alpha level for the mean confidence interval.
Enter trimmed mean percent	Specify the trimmed mean percentage. The percentage is trimmed off each side of the data.

Summary Statistics Options

The red triangle menu next to Summary Statistics contains these options:

Customize Summary Statistics

Select which statistics you want to appear from the list. You can select or deselect all summary statistics. See Additional Summary Statistics.

Show All Modes

Shows all of the modes if there are multiple modes.

Related Information

•	Statistical Details for Summary Statistics