GLZ Quick Specs - Quick Tab
Select the Quick tab of the GLZ Quick Specs dialog box to access the options described here. The specific options that are available on this tab depend on the Type of analysis selected on the GLZ Startup Panel - Advanced tab. For alternative ways of specifying designs in GLZ, see Methods for Specifying Designs.
Element Name | Description |
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Variables | Click the Variables button to display the standard variable selection dialog box. Depending on the Type of analysis selected on the GLZ Startup Panel - Advanced tab, STATISTICA will prompt you to select one or more dependent (response) variables, one or more categorical predictor variables (grouping variables or factors in the design), and/or one or more continuous predictor variables (covariates); if the chosen Distribution on the GLZ Startup Panel - Advanced tab was either Binomial, Multinomial, or Ordinal multinomial, you can also specify an optional Count variable (for aggregated data). For details concerning different types of designs, and the distinction between continuous and categorical predictor variables, see also the Introductory Overview of the GLM module. |
Response codes | Click the Response codes button to display the
Select two codes for the binomial response dialog box, which contains options to select the codes identifying the levels or categories for the categorical (binary) dependent (response) variables. Codes must be integer values or text labels (but can be dates, times, etc.), and at least two codes must be specified. This button is only available if the dependent (response) variables is categorical in nature, i.e., if the chosen Distribution on the
GLZ Startup Panel - Advanced tab was either Binomial, Multinomial, or Ordinal multinomial.
Note: response codes for binomial response variables: When selecting (or specifying via syntax) response codes for binomial response variables (e.g., for logit models), the two selected values (numeric codes or text values) are recoded for the analysis, so that the first code that is specified will be recoded to 1, and the second value will be recoded to 0. For example, if you specified two text values No and Yes, then the first value (No) will be recoded for the analysis to 1, and the parameter estimates can be interpreted with respect to the probability of responding with No; so, if in such an analysis a positive parameter estimate is found for a particular predictor variable x¸ then it means that the more of x the greater is the likelihood of obtaining the response No. Note that the default coding for binomial response variables in the Nonlinear Estimation module may not be the same as that performed in GLZ. One way to verify the particular coding that was performed is to review the spreadsheet of the predicted responses on the Resid 1 tab of the results dialog; that spreadsheet will report in the first column the recoded values (0 or 1) of the response variable.
Note: reference level for categorical dependent (response) variables: The last category (level) specified via the codes will be the reference category for the comparisons with the other categories. So, for example, if a multinomial dependent (response) variable with k = 3 levels is analyzed, the k-1 = 2 parameters for each predictor (effect column) pertain to the comparison of (1) the first level with the last level, and (2) the second level with the last level of the dependent (response) variable.
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Factor codes | Click the Factor codes button to display the Select codes for indep. vars (factors) dialog box, which is used to select the codes identifying the levels for the categorical predictor variables (grouping variables). Codes must be integer values or text labels (but can be dates, times, etc.), and at least two codes must be specified for each categorical predictor variable. This button is only available if categorical predictor variables (grouping variables) were specified for the current analysis. |
Between effects | Click the Between Effects button to display various dialog boxes, depending on the Type of analysis selected on the
GLZ Startup Panel - Advanced tab. If
Factorial ANOVA or
Factorial regression is selected, the
GLM Between Effects (Factorial Design) dialog box will be displayed. If
Nested design ANOVA is selected, the
Nesting for Between-Group Factors dialog box will be displayed. If
Polynomial regression is selected, the
GLM Between Effects (Polynomial Regression) dialog box will be displayed. If General custom designs is selected, the
GLM Between Effects dialog box will be displayed. These dialog boxes are used to specify a custom design for the categorical and continuous predictor variables.
This button is only available if the Type of analysis selected on the GLZ Startup Panel - Advanced tab involves a complex design for the chosen categorical and/or continuous predictor variables. If you selected a simple design, such as Simple regression, then this option may not be available. In that case, if you decide that the design needs to be customized, you can either click the Syntax editor button (in the lower-right corner of the GLZ Quick Specs dialog box) to further customize the model via GLZ Syntax, or you can return to the GLZ Startup Panel - Advanced tab and select General custom designs as the Type of analysis. If the variable selection includes multiple categorical variables, the default design is main effects only. This is reflected in the text displayed in the text box next to the Between effects button.To show more customization options; see the GLZ Quick Specs Dialog - Advanced tab for details. See also, GLZ - Index. |