Paolo -- Here comes my usual response to messages similar to yours:
Following the use of Regression/Linear Models: 1. State your research question in "NATURAL LANGUAGE" not in terms of a "canned statistical name" that may or may not be relevant to your question. 2. Create an ASSUMED MODEL that allows you to translate your "NATURAL LANGUAGE" questions into RESTRICTIONS on your ASSUMED MODEL. 3. Impose the restrictions on your ASSUMED MODEL to obtain your RESTRICTED MODEL and then you have the essentials to test your hypotheses. If this procedure is IDENTICAL to someone's COVARIANCE ANALYSIS then you might want to call yours a COVARIANCE ANALYSIS. -- Joe ******************************** *** Joe H. Ward, Jr. *** 167 East Arrowhead Dr. *** San Antonio, TX 78228-2402 *** Phone: 210-433-6575 *** Fax: 210-433-2828 *** Email: [EMAIL PROTECTED] *** http://www.northside.isd.tenet.edu/healthww/biostatistics/wardindex.html *** ----------- *** Health Careers High School *** 4646 Hamilton-Wolfe *** San Antonio, TX 78229 ********************************* ----- Original Message ----- From: "Morelli Paolo" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Tuesday, September 25, 2001 5:26 AM Subject: Analysis of covariance > HI all, > I have to analyse some clinical data. In particular the analysis is a > comparison between two groups of the mean change baseline to endpoint of a > score. The statistician who planned the analysis used the ANCOVA on the mean > change, using as covariate the baseline values of the scores. > Do you think this analysis is correct? > I thing that in this way we are correcting twice. I think that the right > analysis is an ANOVA on the mean change. > Please let me know your opinion > thanks > Paolo > > > > > ================================================================= > Instructions for joining and leaving this list and remarks about > the problem of INAPPROPRIATE MESSAGES are available at > http://jse.stat.ncsu.edu/ > ================================================================= > ================================================================= Instructions for joining and leaving this list and remarks about the problem of INAPPROPRIATE MESSAGES are available at http://jse.stat.ncsu.edu/ =================================================================
