Thanks for sharing the information. I notice that the interaction between the co-variate and the within subject factor existed in your case. Hence, I wonder if there is any way to do the post hoc tests for the interaction.
Hi, is it possible to use a dichotomous variable as a covariate, or does it have to be continuous? I'm working with test scores, and I'm assigning subjects into groups of alcohol use (high/low). If the covariate has to be continuous, can I use the raw total test scores as a continuous covariate?
Would appreciate your advice - If I have a sample of athletes, say basketball players, and I want to assess the change in a physical measure such as jump height over the course of a tournament, say 8 games, but I want to include individuals playing time on the court, what would the most appropriate statistical test be? As it is not a baseline value would an ANCOVA still be appropriate or is there a way to normalise the jump height scores to account for playing time in each game?Thank you
The covariate does not have to be a baseline value, as long as you have a theoretical justification for using it to reduce the amount unexplained variance in the dependent variable.
I think that it is rather a mixed-model ANCOVA, because you have a diet as a qualitative variable. Pure repeated-measures ANCOVA implies only quantitative dependent variables and quantitative covariates.
Qualitative variable? What do you mean? SPSS is to run quantitative tests. Statistical tests are quantitative. All of those variables as long as they are in the program are quantitative. That's not what mixed models do. It's repeated measures ANCOVA as she says.
Please explain the fields in which you enter the different variables. What is a covariate? What is a fixed factor? This is the thing that confuses students the most. The understanding of the input is as important as the interpretation of the output. Every video focuses on the output but never explain on what basis they entered the inputs. A lengthy detailed video, but doesn't explain the most needed concepts.