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A SAS/IML program for implementing the modified Brown-Forsythe procedure in repeated measures designs
Guillermo Vallejo1, Joaquín Moris, Nélida M Conejo
1Methodology Area, Department of Psychology, University of Oviedo, Plaza Feijóo, s/n, E-33003 Oviedo, Spain. qvallejo@uniovi.es
Computer Methods and Programs in Biomedicine
|August 29, 2006
Summary
This study introduces a new SAS/IML program for analyzing repeated measures data. The program offers a powerful and robust alternative to conventional methods, handling both univariate and multivariate data effectively.
Area of Science:
- Statistics
- Biostatistics
- Computer Science
Background:
- Repeated measures data analysis is crucial in many scientific fields.
- Conventional methods for repeated measures analysis have limitations regarding assumption violations.
- Robust and powerful analytical techniques are needed for complex datasets.
Purpose of the Study:
- To present a novel computer program for analyzing repeated measures data using SAS/IML.
- To provide a robust and powerful alternative to existing analytical solutions.
- To implement a stepwise procedure for comparisons among repeated measurements.
Main Methods:
- Development of a computer program in SAS version 9.1's interactive matrix language (IML).
- Implementation of a new approach for analyzing both univariate and multivariate repeated measures data.
- Inclusion of a Bonferroni inequality-based stepwise procedure for measurement comparisons.
Main Results:
- The new procedure demonstrates comparable power to conventional methods.
- The approach shows increased robustness against violations of underlying assumptions.
- The SAS/IML program effectively analyzes both univariate and multivariate repeated measures data.
Conclusions:
- The developed SAS/IML program provides a valuable tool for researchers analyzing repeated measures data.
- This new approach offers a more robust and powerful alternative, enhancing data analysis reliability.
- The program's utility is demonstrated through a practical numeric example.
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