© American Speech-Language-Hearing Association
Some Issues in the Statistical Analysis of Completely Randomized and Repeated Measures Designs for Speech, Language, and Hearing Research
1 Seton Hall University South Orange, NJ
2 Katholieke Universiteit Leuven Leuven, Belgium
maxludo{at}shu.edu
Contemporary investigators in the areas of speech, language, and hearing rely heavily on inferential statistical procedures to answer both basic and applied research questions. Such statistical procedures typically involve a number of assumptions that need to be fulfilled in order for the procedure to be appropriate for a specific data set. Unfortunately, a review of recent publications in the Journal of Speech, Language, and Hearing Research indicated that some pivotal issues related to those underlying assumptions, although widely discussed and emphasized in the statistical literature, often appear to be neglected in these fields of research. This tutorial therefore addresses two issues that are particularly important for an appropriate and accurate use of some of the most commonly used statistical procedures. The first issue concerns the importance of addressing the sphericity assumption in studies with a repeated measures design. The second issue concerns the definition of the experimental units in a statistical analysis and applies to both completely randomized and repeated measures designs. Theoretical aspects associated with each issue are discussed, and appropriate strategies for data entry and analysis are presented.
KEY WORDS: statistics, sphericity, experimental unit, data analysis, repeated measures design
Submitted on May 20, 1998
Accepted on December 2, 1998
CiteULike 
Connotea 
Delicious 
Digg 
Facebook 
Reddit 
Technorati 
Twitter What's this?
This article has been cited by other articles:
|
|
 |
|
  J. Crukley and S. D. Scollie Children's Speech Recognition and Loudness Perception With the Desired Sensation Level v5 Quiet and Noise Prescriptions Am J Audiol, December 1, 2012; 21(2): 149 - 162. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 L. Girolametto, E. Weitzman, and J. Greenberg Facilitating Emergent Literacy: Efficacy of a Model That Partners Speech-Language Pathologists and Educators Am J Speech Lang Pathol, February 1, 2012; 21(1): 47 - 63. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. E. Shea and S. Curtin Experience, representations and the production of second language allophones Second Language Research, April 1, 2011; 27(2): 229 - 250. [Abstract] [PDF]
|
|
|
|
 |
|
 T. Saltuklaroglu, J. Kalinowski, and A. Stuart Refutation of a Therapeutic Alternative? A Reply to Pollard, Ellis, Finan, and Ramig (2009) J Speech Lang Hear Res, August 1, 2010; 53(4): 908 - 911. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. Heffernan MUMBLING IS MACHO: PHONETIC DISTINCTIVENESS IN THE SPEECH OF AMERICAN RADIO DJs American Speech, March 1, 2010; 85(1): 67 - 90. [Abstract] [PDF]
|
|
|
|
 |
|
 C. Mooshammer, P. Hoole, and A. Geumann Jaw and Order Language and Speech, June 1, 2007; 50(2): 145 - 176. [Abstract] [PDF]
|
|
|
|
 |
|
 S. N. Nair, S. J. Czaja, and J. Sharit A Multilevel Modeling Approach to Examining Individual Differences in Skill Acquisition for a Computer-Based Task J Gerontol B Psychol Sci Soc Sci, June 1, 2007; 62(Special_Issue_1): 85 - 96. [Abstract] [Full Text] [PDF]
|
|