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Use the Insert Categories dialog box to add new categories or other items such as means, totals, to a variable.
To open the Insert Categories dialog box, first open the Edit Variable or New Variable dialog box. From the menu, choose
Available items. This lists all of the possible types of category and other items that you can add to a variable. The following items are available, in addition to any categories and built-in special items in the variable that have been removed from the variable's definition. To add an item, select it and click the >> button.
| Item | Purpose |
|---|---|
| User-defined category | This creates a new category based on a custom expression. After inserting the item, you must define the expression on which the new category is to be based. See the topic Creating a category based on another variable for more information. |
| Base | Shows the total number of cases in the variable. Generally, the base includes every case for which the value stored in the variable is not Null. IBM® SPSS® Data Collection Survey Reporter automatically adds a base to any variable that does not have one, which means that normally you do not need insert a base. See the topic Base Rows and Columns for more information. |
| Unweighted base | Shows the total number of cases in the variable before any weighting has been applied. In an unweighted table, an unweighted base shows the same values as the counts in the base. Only one value is ever shown for an unweighted base, even when multiple types of cell contents have been requested. The value that is shown is the unweighted base count, regardless what type of cell contents have been requested for the table. By default Survey Reporter automatically adds an unweighted base as the first item in the top and side of a weighted table. See the topic Showing the Unweighted Base in Weighted Tables for more information. |
| Mean | Shows the mean value, which is a measure of central tendency. It is the arithmetic average--the sum divided by the number of cases. You can create a mean to show the mean value of a specified numeric variable. Alternatively, you can create a mean to show the mean value of the factors associated with the category and expression items in the axis. See the topic Adding summary statistics to a categorical variable for more information. |
| Minimum | Shows the minimum value of a numeric variable. |
| Maximum | Shows the maximum value of a numeric variable. |
| Standard deviation | Shows a measure of dispersion around the mean. In a normal distribution, 68% of cases fall within one standard deviation of the mean and 95% of cases fall within two standard deviations. For example, if the mean age is 45 with a standard deviation of 10, then 95% of the cases would be between 25 and 65 in a normal distribution. You can show the standard deviation for a specified numeric variable. Alternatively, you can show the standard deviation for the factors associated with the category and expression items in the axis. |
| Standard error | Shows a measure of how much the value of the mean may vary from sample to sample taken from the same distribution. The standard error of the sample mean can be used to estimate a mean value for the population as a whole. In a normal distribution, 95% of the values of the mean should lie in the range of plus or minus two times the standard error from the mean. Additionally, the standard error can be used to roughly compare the observed mean to a hypothesized value of another mean (that is, you can conclude that the two values are different if there is no overlap in the values of the means plus or minus two times the standard error). You can show the standard error for a specified numeric variable. Alternatively, you can show the standard error for the factors associated with the category and expression items in the axis. |
| Sample variance | Shows a measure of dispersion around the mean, equal to the sum of squared deviations from the mean divided by one less than the number of cases. The variance is measured in units that are the square of those of the variable itself. You can show the sample variance for a specified numeric variable. Alternatively, you can show the sample variance for the factors associated with the category and expression items in the axis. |
| Subtotal | The sum of the counts between the most recent base, total, or subtotal, whichever is the most recent, and the next base, total, or subtotal, or the end of the axis, whichever occurs first. A subtotal works in this way regardless of its position in the axis. |
| Total | The sum of the counts between the most recent base or total, whichever is the most recent, and the next total or base, or the end of the axis, whichever occurs first. A total works in this way regardless of its position in the axis. |
| Subheading | A text-only item that can be used to form a subheading. |
| Column text | A text-only item that can be used to form a subheading. When the variable is on the side of the table, the item forms a text-only row. See the topic Adding text rows to tables for more information. |
| Paired preference | Shows the results of a paired preference test. See the topic Adding a Paired Preference Test or a Net Difference Test for more information. |
| Derived category | Shows a derived category calculated from other categories within the variable using an arithmetic expression. See the topic Creating a category based on other categories for more information. |
| Numeric | This creates a new item based on a numeric variable. You can use this to create a summary variable that references a number of other variables. |
| Sum | Shows the sum or total of the values in a specified numeric variable. |
| Effective base | Displays the effective base. This is calculated by dividing the squared sum of weights for all of the respondents in the table by the sum of the squared weights. |
| Net difference | Displays the result of a net difference test. |
| Median | Displays the median for a numeric variable. |
| Percentile | Displays a percentile for a numeric variable. |
| Mode | Displays the mode for a numeric variable. |
| T-Value | Determines whether the mean of a numeric variable is significantly different from zero or some other specified value. See the topic T-test Test for more information. |
| T-Probability | Determines whether or not there is a relationship between the data being tested. Refer to T-test Test and p Values for more information. |
For more advanced information about the items you can enter, see Element Syntax.
When calculating the values for mean, standard deviation, standard error, sample variance, minimum, and maximum items, Survey Reporter uses the same formulae used for the cell contents. See the topic Formulae for Cell Contents for more information.
Items to insert. Lists the items in the order in which they will be displayed. To remove an item, select it and click the >> button.
Move up/Move down. Select an item in the Items to insert list and choose the Move up or Move down button to change the order in which the categories will be inserted into the variable.
Description. Displays an automatically generated description for the category, which you can change to show a meaningful description. Category descriptions appear in your tables and charts if you have chosen to display them instead of category names. See the topic Changing the description for a category for more information.
Decimals. Displays the default number of decimal places for the type of item selected.
Edit Item This button is available when you select a category that supports expressions. Choose this button to open the Edit User-Defined Item dialog box or Edit Derived Category dialog box where you can enter a definition for the category.