Workspace Node: Descriptive Statistics - Results - Advanced Tab / In-Database Descriptive Statistics - Specifications - Advanced Tab
In the Descriptive Statistics node dialog box, under the Results heading, select the Advanced tab to access the following options.
In the In-Database Descriptive Statistics node dialog box, under the Specifications heading, select the Advanced tab to access the following options. The In-Database Descriptive Statistics node enables users to obtain descriptive statistics about the data in the database table. The node provides a subset of functionality as compared with the common Descriptive Statistics node. It is generally difficult to run rank statistics in database. In most cases it requires sorting of all data, which is not a performance efficient process. The implementation of median and percentiles in the In-Database Descriptive Statistics node follows the Closest Observation method for percentile calculation.
Variables. (This option is available only in the In-Database Descriptive Statistics node dialog box.) Click the Variables button to display a variable selection dialog box.
Summary: Statistics. Select this check box to produce a spreadsheet with the descriptive statistics for all of the previously selected variables (via the Variables button on the Specifications - Quick tab).
G1. (This option is not available in the In-Database Descriptive Statistics node dialog box.) Select this check box to create a compound graph for each selected variable consisting of a histogram, normal probability plot, box plot, and descriptive statistics. This is a quick way to visually see the distribution of the data.
G2. (This option is not available in the In-Database Descriptive Statistics node dialog box.) Select this check box to create a compound graph for each selected variable consisting of a histogram, horizontal box plot, and descriptive statistics. This compound graph contains more descriptive statistics such as variance, skewness, and 95% prediction for observation.
Compute statistics. The options selected in these fields will determine which statistics will be computed when the Summary: Statistics check box is selected. Refer to the Introductory Overview for a discussion of the most common descriptive statistics and their interpretation.
- Location, valid N
- Select the check box next to the statistics you want computed. The statistics in this group box are used to estimate the location of the distribution as well as to determine the number of valid cases for each selected variable (Valid N and Percent of Valid Observation). You can estimate a variety of location statistics including Mean, Sum, Median, Mode, Geometric mean, and Harmonic mean. (Valid N, Mean, Sum, and Median are available in the In-Database Descriptive Statistics node dialog box.)
- Variation, moments
- Select the check box next to the statistics you want computed. The statistics in this group box are used to estimate the variation for the variable as well as a variety of its moments and their standard errors. You can specify to estimate the Standard Deviation, CI for Sample SD Interval, Coefficient of Variation, Variance, Standard error of the mean, and Confidence limits for means. When computing confidence levels, you must specify the confidence Interval via the edit box. Refer to the Introductory Overview for a basic discussion of confidence limits. You can also calculate the Skewness and its Standard error as well as the Kurtosis and its Standard error. (Standard deviation, Variance, Skewness, and Kurtosis are available in the In-Database Descriptive Statistics node dialog box.)
- Percentiles, ranges
- Select the check box next to the statistics you want computed. The options in this group box are used to estimate a variety of percentiles and ranges for each variable. You can specify to compute
Minimum & maximum values,
Lower & upper quartiles, and Percentile boundaries. (Range and
Quartile range options are also available in the
Descriptive Statistics node dialog box.)
Note: Computation of median and quartiles (25th, 50th, and 75th percentiles). When the distribution of values cannot be exactly divided into halves and quartiles, there are different ways to compute the respective median and quartile values (and percentiles). The specific method of computation for those values can be configured "system-wide" via the Computations of percentiles option in the Options dialog box - Analyses/Graphs: Limits tab.
Select all stats. Click this button to select all the statistics on this tab.
Reset. Click this button to clear all but the default statistics on this tab. The default statistics are Valid N, Mean, Standard Deviation, and Minimum & Maximum.
Options / C / W. See Common Options.
OK. Click the OK button to accept all the specifications made in the dialog box and to close it. The analysis results will be placed in the Reporting Documents node after running (updating) the project.