help
help > RE: repeated measures
Sep 6, 2017 02:09 AM | Andrew Zalesky
RE: repeated measures
Hi Jay,
I assume you mean by CT2=CT1 the null hypothesis of controls do not differ between the two time points.
In the case, you can use a standard repeated measures t-test and exclude the patients from the analysis completely.
There is an example of a repeated measures t-test in the Help menu.
For the null of CT1=PT1, this is a standard t-test. No need for exchange blocks here and your design matrix will just have two columns.
I hope this is clear.
Andrew
Originally posted by Jaykumar Grandhi:
I assume you mean by CT2=CT1 the null hypothesis of controls do not differ between the two time points.
In the case, you can use a standard repeated measures t-test and exclude the patients from the analysis completely.
There is an example of a repeated measures t-test in the Help menu.
For the null of CT1=PT1, this is a standard t-test. No need for exchange blocks here and your design matrix will just have two columns.
I hope this is clear.
Andrew
Originally posted by Jaykumar Grandhi:
Hi Andrew,
Thanks for the help! How would I structure the inputs if I wanted the following null hypotheses:
Ho(1) CT2 = CT1
Ho(2) CT1 = PT1
I was reading about the cell mean method and came up with the following: (C-control, P-patient)
Design
CT1 CT2 PT1 PT2
C1T1 1 0 0 0
C1T2 0 1 0 0
C2T1 1 0 0 0
C2T2 0 1 0 0
P1T2 0 0 1 0
P1T2 0 0 0 1
P2T1 0 0 1 0
P2T2 0 0 0 1
and then the contrast would be:
Ho(1) contrast [1 -1 0 0]
Ho(2) contrast [1 0 -1 0]
I understand that I cannot subtract the within-subject means due to rank deficiency.
Is it appropriate to still use exchange blocks as such: 1 1 2 2 3 3 4 4?
Thanks!
Thanks for the help! How would I structure the inputs if I wanted the following null hypotheses:
Ho(1) CT2 = CT1
Ho(2) CT1 = PT1
I was reading about the cell mean method and came up with the following: (C-control, P-patient)
Design
CT1 CT2 PT1 PT2
C1T1 1 0 0 0
C1T2 0 1 0 0
C2T1 1 0 0 0
C2T2 0 1 0 0
P1T2 0 0 1 0
P1T2 0 0 0 1
P2T1 0 0 1 0
P2T2 0 0 0 1
and then the contrast would be:
Ho(1) contrast [1 -1 0 0]
Ho(2) contrast [1 0 -1 0]
I understand that I cannot subtract the within-subject means due to rank deficiency.
Is it appropriate to still use exchange blocks as such: 1 1 2 2 3 3 4 4?
Thanks!
Threaded View
| Title | Author | Date |
|---|---|---|
| Jaykumar Grandhi | Aug 19, 2017 | |
| Andrew Zalesky | Aug 21, 2017 | |
| Jaykumar Grandhi | Aug 22, 2017 | |
| Andrew Zalesky | Aug 23, 2017 | |
| Jaykumar Grandhi | Sep 5, 2017 | |
| Andrew Zalesky | Sep 6, 2017 | |
| Jaykumar Grandhi | Aug 23, 2017 | |
| Andrew Zalesky | Aug 23, 2017 | |