Association Rules Results - Quick Tab

Select the Quick tab of the Association Rules Results dialog box to access options to review the association rules in tabular and graphical format.

Association rules

Click this button to display a results spreadsheet summarizing the final association rules. As described in Computational Procedures and Terminology, association rules are generated of the general form if Body then Head, where Body and Head stand for single codes or text values (items) or conjunctions of codes or text values (items; e.g., if (Car=Porsche and Age<20) then (Risk=High and Insurance=High). The major statistics computed for the association rules are Support (relative frequency of the Body or Head of the rule), Confidence (conditional probability of the Head given the Body of the rule), and Correlation (support for Body and Head, divided by the square root of the product of the support for the Body and the support for the Head, see Computational Procedures and Terminology). These statistics are summarized in this spreadsheet. The values for support, confidence, and correlation are expressed in percent. Note that the rules in the results spreadsheet can easily be sorted by any column, using the standard Data - Sort facilities of Statistica.

Frequent itemsets

Click this button to display a results spreadsheet showing the individual item sets that are contained in the Body and Head portions of the final association rules. Specifically, the spreadsheet will report, for each item set, the frequency with which it was encountered, and the Support value, expressed in percent. For details, see also Computational Procedures and Terminology.

Min head size; Max head size

These parameters determine the minimum and maximum complexity ("size") of the association rules to be included in the rule network graphs. When there are many thousands of rules consisting of many items, the network graphs can become difficult to read (because they contain too many rules). In that case, you may specify the minimum and maximum complexity (size) of rules to be included in the graphs. For example, if you set the Min head size to 2, then only rules involving two or more items (depending on the setting of the Max head size parameter) in the head portion of the respective rules will be displayed (e.g., if X then (Y and Z) ). If no rules satisfy the Min head size and Max head size criteria you specified, no rules will be shown in the graphs.

Rule network

Click this button to display a graphical summary of the set of final association rules, i.e., of the final association rules network (see also Graphical Representation of Associations). In this graph, the support values for the Body and Head portions of each association rule are indicated by the sizes and colors of each circle (see also Computational Procedures and Terminology). The thickness of each line indicates the confidence value (conditional probability of Head given Body) for the respective association rule; the sizes and colors of the circles in the center, above the Implies label, indicate the joint support (for the co-occurrences) of the respective Body and Head components of the respective association rules.

3D Rule network

Click this button to display a 3D graphical summary of the set of final association rules, i.e., of the final association rules network (see also Graphical Representation of Associations). As in the Rule network, in this graph the support values for the Body and Head portions of each association rule are indicated by the sizes and colors of each circle in the 2D plane (see also Computational Procedures and Terminology). The thickness of each line indicates the confidence value (joint probability) for the respective association rule; the sizes and colors of the "floating" circles plotted against the (vertical) z-axis indicate the joint support (for the co-occurrences) of the respective Body and Head components of the association rules. The plot position of each circle along the vertical z - axis indicates the respective confidence value.

For additional details, see also Tabular Representation of Associations and Graphical Representation of Associations. For general information, see  Computational Procedures and Terminology.