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help > RE: Between & Within subjects design for Repeated Measures
Apr 4, 2019 12:04 AM | Daniel Brennan - Icahn School of Medicine at Mount Sinai; New York University
RE: Between & Within subjects design for Repeated Measures
The data is public, so already collected!
I was originally thinking/hoping to leverage the power of the 4 observations in the between-subjects hypothesis, but it seems that collapsing is the only way to model the between-subject variance effectively.
I am also interested in the within-subject variance, so this thread has been immensely helpful.
Thanks again,
Daniel
Originally posted by Andrew Zalesky:
I was originally thinking/hoping to leverage the power of the 4 observations in the between-subjects hypothesis, but it seems that collapsing is the only way to model the between-subject variance effectively.
I am also interested in the within-subject variance, so this thread has been immensely helpful.
Thanks again,
Daniel
Originally posted by Andrew Zalesky:
You could either collpase as you describe below
or use the design matrix that you gave in your previous post.
Both seem reasonable. However, the design matrix in your previous post will model variances across-sessions (i.e. intra-subject), which is irrelevant to your hypothesis. I.e. you don't need intra-subject variance for your hypothesis, so this might be superfluous. Give both options a try...
ginally posted by Daniel Brennan:
Both seem reasonable. However, the design matrix in your previous post will model variances across-sessions (i.e. intra-subject), which is irrelevant to your hypothesis. I.e. you don't need intra-subject variance for your hypothesis, so this might be superfluous. Give both options a try...
ginally posted by Daniel Brennan:
Hi Andrew,
Yes, that's what I'm doing for the within-subject variation. I'm interested if differences across individuals, accounting for their own intra-subject variation, are associated with a certain Independent variable.
As an example, lets say we had a measure of cognitive performance measured across the 4 timepoints. We could look at how the within-subject variation in the task is related to within-subject variation of connectivity in the way you've suggested, by modeling the subject means.
However, I'm also interested in the connectivity of individuals who perform better overall compared to others. A simple way, I believe, would be to take the collapse the connectivity and performance across 4 timepoints, and treat those as 19 IV's and DV's. However, I'm wondering if there is a more elegant way which considers the intra-subject variability as well.
Thank you so much in advance for your help and time. Your help is instrumental in so many projects, mine included!
Yes, that's what I'm doing for the within-subject variation. I'm interested if differences across individuals, accounting for their own intra-subject variation, are associated with a certain Independent variable.
As an example, lets say we had a measure of cognitive performance measured across the 4 timepoints. We could look at how the within-subject variation in the task is related to within-subject variation of connectivity in the way you've suggested, by modeling the subject means.
However, I'm also interested in the connectivity of individuals who perform better overall compared to others. A simple way, I believe, would be to take the collapse the connectivity and performance across 4 timepoints, and treat those as 19 IV's and DV's. However, I'm wondering if there is a more elegant way which considers the intra-subject variability as well.
Thank you so much in advance for your help and time. Your help is instrumental in so many projects, mine included!
Threaded View
| Title | Author | Date |
|---|---|---|
| Daniel Brennan | Apr 2, 2019 | |
| Andrew Zalesky | Apr 3, 2019 | |
| Daniel Brennan | Apr 3, 2019 | |
| Andrew Zalesky | Apr 3, 2019 | |
| Daniel Brennan | Apr 4, 2019 | |
| Daniel Brennan | Apr 3, 2019 | |
| Andrew Zalesky | Apr 3, 2019 | |