General Linear Models (GLM) and Quick Tab

Ribbon bar. Select the Statistics tab. In the Advanced/Multivariate group, click Advanced Models and from the menu, select General Linear to display the General Linear Models (GLM) dialog box.

Classic menus. On the Statistics - Advanced Linear/Nonlinear Models submenu, select General Linear Models to display the General Linear Models (GLM) dialog box.

This dialog box contains one tab: Quick. Use these options to select the desired method of analysis (see also, General Linear Models Index). See also, Data Mining with Statistica.

For more information, refer to the Introductory Overview and the examples. See also GLM - Index, or Methods for Analysis of Variance. For related ANOVA and regression methods, refer also to DOE and Variance Components.

OK. Click the OK button to display the appropriate analysis specification dialog box, depending on the Specification method selected on the Quick tab.

Cancel. Click the Cancel button to close the dialog box without performing an analysis.

Options. See Options Menu for descriptions of the commands on this menu.

Open Data. Click the Open Data button to display the Select Data Source dialog box, which contains options to choose the spreadsheet on which to perform the analysis. The Select Data Source dialog box contains a list of the spreadsheets that are currently active.

Select Cases. Click the Select Cases button to display the Analysis/Graph Case Selection Conditions dialog box, which contains options to create conditions for which cases will be included (or excluded) in the current analysis. More information is available in the case selection conditions overview and syntax summary.

W. Click the W (Weight) button to display the Analysis/Graph Case Weights dialog box, which contains options to adjust the contribution of individual cases to the outcome of the current analysis by "weighting" those cases in proportion to the values of a selected variable.

Weighted moments. This module can use fractional case weights in most computations. Some other modules use case weights as integer case multipliers or frequency values. In this module, when the Weighted moments check box is selected, each observation contributes the weighting variable's value for that observation. The weight values need not be integers.

DF = W-1 / N-1. When the Weighted moments check box is selected, moment statistics (e.g., mean, variance) can be based on the sum of the weight values for the weighting variable (W-1), or on the number of (unweighted) observations (N-1). The sums of squares and cross products will always be based on the weighted values of the respective observations. However, in computations requiring the degrees of freedom (e.g., standard deviation, ANOVA tables, etc.), the value for the degrees of freedom can either be computed as the sum of the weight values minus one, or as the number of observations minus one. Moment statistics are based on the sum of the weight values for the weighting variable if the W-1 option button is selected, and are based on the number of (unweighted) observations if the N-1 option button is selected. For more information on options for using integer case weights, see Selecting a Weighting Variable.

 

Quick Tab

The Quick tab of the General Linear Models (GLM) dialog box presents a list of common experimental and regression analysis designs in the Type of analysis list (see the Introductory Overview). In order to perform a general linear model analysis, a data file must be selected. This tab provides access to the three different user interfaces available in the STATISTICA General Linear Models module (in the Specification method list; these types of user interfaces are also available in STATISTICA General Regression Models, Generalized Linear/Nonlinear Models, General Partial Least Squares Models, General Discriminant Analysis Models, and ANOVA; see also Methods for Analysis of Variance).

Type of analysis. Select the type of design that you want to perform from the Type of analysis list. Note that all types of designs can be specified via the General linear models option. For more information on a particular type of analysis, click on the following links. See also the Introductory Overview topic: Types of Analyses.

Specification method. The Specification method list presents the three alternative user-interfaces available in GLM (as well as GRM, GLZ, PLS, GDA, and ANOVA). You can choose among the three different user interfaces in the Specification method list only when General linear models is selected as the Type of analysis. When any other Type of analysis is selected, you must use Quick specs dialog.

Quick specs dialog. Select Quick specs dialog to display the respective Quick Specs dialog box corresponding to the current selection in the Type of analysis list. The Quick Specs dialog box will prompt you to select dependent variable(s) and categorical and/or continuous predictor variables (depending on the selection in the Type of analysis list), and construct a default model. Use the Quick Specs Dialog - Options tab to modify various computational details, or the Syntax editor button on the Quick specs dialog box to further customize the model via GLM Syntax.

Analysis Wizard. Select Analysis Wizard to display a sequence of dialog boxes that will guide you through the steps for specifying an analysis. At the conclusion of the sequence of dialog boxes, you can either compute the results or click the Syntax editor button in the GLM Analysis Wizard Extended Options dialog box to further customize the model via command syntax, open an existing file with command syntax, or save syntax in a file for future repetitive use. Note that selecting Analysis Wizard automatically moves the Type of analysis selection to General linear models. You cannot use the Analysis Wizard with any other type of analysis.

Analysis syntax editor. Select Analysis syntax editor to specify a model via the GLM Analysis Syntax Editor. This editor provides various options for specifying designs and for modifying various parameters of the computational procedures. You can also open an existing text file with command syntax, or save syntax in a file for future repetitive use. Refer to the description of GLM Syntax for addition details. Note that selecting Analysis syntax editor automatically moves the Type of analysis selection to General linear models. You cannot use the Analysis syntax editor with any other type of analysis.

For more information, refer to the GLM Introductory Overview and the examples. See also GLM - Index or Methods for Analysis of Variance.