Statistics Function -- Data & Analyses Selection Tab

 

The Statistics function enables you to describe the distribution of a data set.  Currently the Statistics function performs percentile and histogram analyses on the data columns, as well as providing basic statistics about data columns.  The Statistics function operates on the data set as it currently appears in the table; if some of the data has been filtered and is not shown, it will not be included in the analyses.  Select the Statistics (Statistics function button) toolbar button in the Data Table Window to present the Statistics window:  

Sample screen shot of Data & Analyses Selection tab

The Statistics window uses five tabs, but you must first complete the information on the Data & Analyses Selection tab before working on the other tabs.  In the Analyses to Perform group box,  first choose which new table types will be created:

If you have checked the Basic Statistics check box in the Analyses to Perform group box, then complete the information in the Basic Statistics group box.  Type a title for the new table in the Tab Name field.  By default, the statistics of interest (minimum, maximum, sum, mean, median, standard deviation, skew, and kurtosis) are all initially checked, but you may click on the check boxes to de-select some of the statistics.

In the Columns to Analyze group box, you must also choose the data columns that should be analyzed.  By default, all columns are selected.  Click the Select button to present the Include/Exclude Columns window:

Include/Exclude Columns screen shot

The list on the Include/Exclude Columns window shows all of the column names and whether or not the columns should be included in the analyses.  A check in the "Include?" column indicates that a given column will be analyzed.  You may directly check and un-check the check boxes by clicking the mouse in them.  Use the vertical scroll bar on the right to move up and down through the table of column names.  Click the Invert button to automatically de-select the blue rows and select those that were white.

Users may also choose to include or exclude columns whose names meet certain criteria:

  1. First specify whether or not to select columns based on all or any of the criteria to be specified (not important if only a single criterion will be used).  Check the Match using: ALL criteria or ANY criteria radio button to reflect whether the selection should be set for this "And" or "Or" condition.

  2. Click the Add Criteria button to add a row to the table below the Column Name, Operation, and Value column headings.  Each row represents a filter condition.  Click the Delete Criteria button to remove any criteria that are selected (shown in blue). To select a single criterion, click the mouse on any entry in that row. To select multiple criteria (in an MS-Windows operating system), hold the control key down while clicking the mouse.

  3. On this screen the Column Name column is always titled Column Name.  This indicates that the criterion will reflect a characteristic of the column name.  Click the mouse on the second cell in the first white or blue row of the table (under the Operation column) to present a pull-down menu appear.  The menu shows a list of operations that apply to numeric, logical, and string variables (>, <, >=, <=, =, not =, starts with, does not start with, contains, does not contain, ends with, and does not end with); choose the one to use for selecting a group of columns.  Complete the selection statement by typing directly into the cell in the Value column.

  4. Then click the Select button to highlight in blue those rows whose column names match the criteria.  Click the Include or Exclude buttons to change all of the selected check boxes under the "Include?" column. 

Click OK to add the names of the included columns beneath the Columns to Analyze: label  on the Statistics interface.  Click OK to complete the action and close the Include/Exclude Columns window. Click Cancel to close the Include/Exclude Columns window without making any changes.

After you complete the selections on the Data & Analyses Selection tab of the Statistics window, click OK only if no Percentiles, Histogram, Correlation, or Regression analyses are to be performed.  To set the parameters for the Percentiles, Histogram, Correlation, and Regression analyses, click on the Percentile, Histogram, Correlation, and Regression tabs to specify the parameters for the analysis.