Summarize Columns

The Tables > Summary command calculates various summary statistics, including the mean and median, standard deviation, minimum and maximum value, and so on.

In a summary table:

•	A single row exists for each level of a grouping variable that you specify. If no grouping variable is specified, a single row exists for the full data table.

•	When there are several grouping variables, the table contains rows for each combination of levels of all the grouping variables.

•	In addition to one column for each grouping variable, the table contains frequency counts in a column named N Rows with counts for each grouping level.

•	The summary table can be linked to its source table. When you select rows in the summary table, the corresponding rows are highlighted in its source table.

•	If the source table’s column(s) contain value labels, the value labels are displayed in the new table.

•	A summary table is not saved when you close it unless you select File > Save As to give it a name and location.

Create a Summary Table

To create a summary table

1.	Open a data table.

2.	Select Tables > Summary.

3.	Highlight the columns that you want to summarize.

Note: For details about the options in the red triangle menu, see Columns Filter Menu in JMP Platforms.

4.	Add summary statistics, groups, subgroups, and select any options needed:

‒	Add Summary Statistics

‒	Use One or More Grouping Columns

‒	Use Quantile Statistics

‒	Change the Format of the Statistics Column Name

‒	Link to the Original Data Table

‒	Keep the Summary Window Open

‒	Create a Two-Way Table of Summary Statistics by Adding a Subgroup Variable

5.	Name the summary table by typing a name in the box beside Output table name.

Click OK.

Add Summary Statistics

You can add columns that display summary statistics (such as mean, standard deviation, median, and so on) for any numeric column in the source table.

1.	In the Summary window, highlight the column that you want to use in calculating the statistics.

2.	Click the Statistics button.

3.	Select one of the standard univariate descriptive statistics from the Statistics drop-down menu. The statistics are described in Explanation of Statistics.

Use One or More Grouping Columns

If you want the statistics summarized by group, highlight the column(s) that you want to be your grouping variables and click Group to move the variable into the grouping variables list. See Example of Creating a Summary Table, for an example. If you add only grouping variables, the summary table shows a count for each group.

To change the order of the grouping variables

To change the order of the grouping variables (ascending or descending order), select a variable in the grouping variable list and click the ascending or descending button (

). The icon beside the variable changes to indicate the sorting order.

You can also change the order of the grouping variables using the Value Ordering column property. See Value Ordering in The Column Info Window.

To include marginal statistics

To add marginal statistics (for the grouping variables) to the output columns, click the box beside Include marginal statistics. In addition to adding marginal statistics for each grouping variable, JMP adds rows at the end of the table that summarize each level of the first grouping variable. For example, proceed as follows:

1.	Open the Companies.jmp sample data table.

2.	Select Tables > Summary.

3.	Select Profits ($M) and click Statistics.

4.	Select Mean.

5.	Select Type and Size Co and click Group.

6.	Select Include marginal statistics.

7.	Click OK (or Create). See Summary Table with and without Marginal Statistics at left.

Summary Table with and without Marginal Statistics

Compare the summary table with marginal statistics (at left) to the summary table without marginal statistics (at right). You can see that the marginal statistics are added, and a row showing that there are 32 total Computer and Pharmaceutical companies.

Use Quantile Statistics

To add specific quantile statistics, follow these steps:

1.	In the box under For quantile statistics, enter value (%) type the desired quantile value (%) for the first quantile (for example, 25).

2.	Select the applicable column and click Statistics.

3.	Select Quantiles.

4.	(Optional) Repeat this process for any additional quantiles.

Change the Format of the Statistics Column Name

To change the format of the statistics column name in the summary table, select from one of the formats in the statistics column name format menu. Statistics Column Name Format Options and Examples illustrates the available options. Assume that you are creating a summary table of the mean profits for a company. Your original column name is Profits ($M).

Statistics Column Name Format Options and Examples
Option	Example
stat (column)	Mean (Profits ($M))
column	Profits ($M)
stat of column	Mean of Profits ($M)
column stat	Profits ($M) Mean

Link to the Original Data Table

You can select whether to link the summary table to the original data table. By default, the Link to original data table option is selected. If you want to edit the data in the summary table, deselect the Link to original data table option. When the summary table is linked to the original data table, you cannot edit the data in the summary table, since that would modify and compromise the original data.

Within linked tables, if you drag columns from the summary table into the column heading of a new column in the original data table, the values are expanded as if they were matched by grouping columns.

Keep the Summary Window Open

If you select the Keep dialog open option, the Summary window remains open after you click Create. Notice that once you select this option, the OK button is replaced by a Create button.

Create a Two-Way Table of Summary Statistics by Adding a Subgroup Variable

1.	Highlight the column(s) that you want to be the nested variable(s). These are your “subgroup variable(s).”

2.	Click Subgroup to move the variable(s) into the subgroup list.

3.	Highlight the column for which you want statistics summarized by subgroup.

4.	In the Statistics list, select the specific statistic that you want.

Click OK.

For details about the types of statistics, see Explanation of Statistics.

Add a Statistics Column to an Existing Summary Table

After you have created a summary table, you can add columns of descriptive summary statistics for any numeric column in the source table. To do so, from an existing summary table, click on the upper red triangle in the data grid and select Add Statistics Column.

Example of Adding a Statistics Column to an Existing Table

Suppose that you have already created a summary table, and you want to add more statistics to the existing summary table.

1.	Open the Companies.jmp sample data table.

2.	Select Tables > Summary.

3.	Select Type and Size Co and click Group.

Click OK.

5.	From the red triangle menu in the upper left corner of the data table grid, select Add Statistics Column.

Creating a Summary Statistics Column from Within a Data Table

A modified version of the Summary window appears.

6.	Select the column that you want, click Statistics, and select the specific statistic that you want. For this example, select profit/emp and click Statistics, and then select Mean.

Click OK.

Example of a Summary Table with a Summary Statistics Column

The Mean(profit/emp) column is added to the existing summary table.