The TCALIS Procedure |
Guide to the Advanced Skills Level |
At the advanced level, you learn to use the advanced data analysis and output control tools supported by PROC TCALIS.
The following advanced data analysis topics are discussed:
Assessment of fit
The section Assessment of Fit presents the fit indices used in PROC TCALIS. However, the more important topics covered in this section are about how model fit indices are organized and used, how residuals can be used to gauge the fitting of individual parts of the model, and how the coefficients of determination are defined for equations.
To customize your fit summary table, you can use the options on the FITINDEX statement.
Effect partitioning
The section Total, Direct, and Indirect Effects discusses the total, direct, and indirect effects and their computations. The stability coefficient of reciprocal causation is also defined.
To customize the effect analysis, you can use the EFFPART statement.
Counting and adjusting degrees of freedom
The section Counting the Degrees of Freedom describes how PROC TCALIS computes model fit degrees of freedom and how you can use some options on the PROC TCALIS statement to make degrees-of-freedom adjustments.
To adjust the model fit degrees of freedom, you can use the DFREDUCE= and NOADJDF options in the PROC TCALIS statement.
Standardized solutions
Standardization schemes used in PROC TCALIS are described and discussed in the section Standardized Solutions.
Standardized solutions are displayed by default. You can turn them off by using the NOSTAND option of the PROC TCALIS statement.
Model modifications
In the section Modification Indices, modification indices such as Lagrange multiplier test indices and Wald statistics are defined and discussed. These indices can be used either to enhance your model fit or to make your model more precise.
To limit the modification process only to those parameters of interest, you can use the LMTESTS statement to customize the sets of LM tests conducted on potential parameters.
A Priori Parametric Function Testing
You can use the TESTFUNC statement to test a priori hypotheses individually. You can use the SIMTEST statement to test a priori hypotheses simultaneously.
To be more effective in presenting your analysis results, you need to be more sophisticated in controlling your output. Some customization tools have been discussed in the previous section Advanced Data Analysis Tools and might have been mentioned in the examples included in the basic and the intermediate levels. In the following topics, these output control tools are presented in a more organized way so that you can have a systematic study scheme of these tools.
Global output control tools in PROC TCALIS
You can control output displays in PROC TCALIS either by the global display options or by the individual output printing options. Each global display option typically controls more than one output display, while each individual output display controls only one output display. The global display options can both enable and suppress output displays, and they can also alter the format of the output.
See the ALL, PRINT, PSHORT, PSUMMARY, and NOPRINT options for ways to control the appearances of the output. See the section Global Display Options for details about the global display options and their relationships with the individual output display options. Also see the ORDERALL, ORDERGROUPS, ORDERMODELS, ORDERSPEC, PARMNAME, PRIMAT, NOORDERSPEC, NOPARMNAME, NOSTAND, and NOSE options which control the output formats.
Customized analysis tools in PROC TCALIS
Many individual output displays in PROC TCALIS can be customized via specific options or statements. If you do not use these customization tools, the default output will usually contain a large number of displays or displays with very large dimensions. These customized analysis tools are as follows:
The ON=, OFF=, ON(ONLY)= options in the FITINDEX statement enable you to select individual or groups of model fit indices or modeling information to display. You can still save the information of all fit indices in an external file by using the OUTFIT= option.
The EFFPART statement enables you to customize the effect analysis. You display only those effects of substantive interest.
The LMTESTS statement enables you to customize the sets of LM tests of interest. You test only those potential parameters that are theoretically and substantively possible.
Output selection and destinations by the ODS system
This kind of output control is used not only for PROC TCALIS, but is used for all procedures that support the ODS system. The most common uses include output selection and output destinations assignment. You use the ODS SELECT statement together with the ODS table names or graph names to select particular output displays. See the section ODS Table Names for these names in PROC TCALIS.
The default output destination of PROC TCALIS is the listing destination. You can add or change the destinations by using statements such as ods html (for html output), ods rtf (for rich text output), and so on. For details, see
Chapter 20,
Using the Output Delivery System.
Note: This procedure is experimental.
Copyright © 2009 by SAS Institute Inc., Cary, NC, USA. All rights reserved.