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RegisterTRT|RTR rulez? Really? [RSABE / ABEL]
Dear Dan, ElMaestro and Helmut!
Rulez? Really?
Read chapter 9.3 of Chow and Liu, especially 9.3.4 "Assessment of Intra-Subject Variabilities". And if you have, read it again.
For me the consequence of this chapter is: While it is true that this design has the advantage of allowing the separate estimation of the intra-subject variabilities of Reference and Test, there is no valid way to evaluate T versus R in case of heteroscedasticity. And this renders the advantage useless.
A valid evaluation with GLM-ANOVA or even with intra-subject contrasts, which in other replicate designs is able to deal with different variabilities, has to assume s2wT=s2wR.
If this is also the case for evaluation via mixed model software is left for discussion. But at least in the EMA jurisdiction doesn't allow for it if we take the Q&A literally and translate 'not recommended' into 'not allowed'.
Which one do you mean?
Rulez? Really?
Read chapter 9.3 of Chow and Liu, especially 9.3.4 "Assessment of Intra-Subject Variabilities". And if you have, read it again.
For me the consequence of this chapter is: While it is true that this design has the advantage of allowing the separate estimation of the intra-subject variabilities of Reference and Test, there is no valid way to evaluate T versus R in case of heteroscedasticity. And this renders the advantage useless.
A valid evaluation with GLM-ANOVA or even with intra-subject contrasts, which in other replicate designs is able to deal with different variabilities, has to assume s2wT=s2wR.
If this is also the case for evaluation via mixed model software is left for discussion. But at least in the EMA jurisdiction doesn't allow for it if we take the Q&A literally and translate 'not recommended' into 'not allowed'.
❝ BTW, if you like a reference that’s a design the two Lászlós used in some of their papers / simulations.
Which one do you mean?
—
Regards,
Detlew
Regards,
Detlew
Complete thread:
- 3-per, 2-trt designs and estimation of intra-subj. variance ElMaestro 2013-08-12 19:54 [RSABE / ABEL]
![[Mix]](https://static.bebac.at/img/mix.png "open in Mix view")
- 3-per, 2-trt designs and estimation of intra-subj. variance Dr_Dan 2013-08-13 10:11
- 3-per, 2-trt designs and estimation of intra-subj. variance ElMaestro 2013-08-13 15:00
- TRT|RTR rulez! Helmut 2013-08-13 18:23
- TRT|RTR rulez? Really?d_labes 2013-08-14 08:16
- TRT|RTR rulez? Really? Yes. ElMaestro 2013-08-14 11:29
- TRT|RTR rulez? Really? No. d_labes 2013-08-14 13:34
- TRT|RTR rulez? Really? No. ElMaestro 2013-08-14 14:25
- TRT|RTR Lost in formulas. d_labes 2013-08-14 16:35
- TRT|RTR rulez? Really? No. ElMaestro 2013-08-14 14:25
- TRT|RTR rulez? Really? No. d_labes 2013-08-14 13:34
- TRT|RTR rulez? References Helmut 2013-08-14 13:44
- References László & László d_labes 2013-08-14 19:12
- Heteroscedasticity Helmut 2013-08-17 17:33
- Heteroscedasticity: TRT|RTR rulez! d_labes 2013-08-29 16:45
- Heteroscedasticity: TRT|RTR rulez! ElMaestro 2013-08-29 17:50
- Sims & evaluation d_labes 2013-08-30 09:16
- Sims & evaluation ElMaestro 2013-08-31 14:11
- Evaluation subtleties d_labes 2013-08-31 17:20
- Sims & evaluation ElMaestro 2013-08-31 14:11
- Sims & evaluation d_labes 2013-08-30 09:16
- Heteroscedasticity: TRT|RTR rulez! ElMaestro 2013-08-29 17:50
- Heteroscedasticity: TRT|RTR rulez! d_labes 2013-08-29 16:45
- Heteroscedasticity Helmut 2013-08-17 17:33
- References László & László d_labes 2013-08-14 19:12
- TRT|RTR rulez? Really? Yes. ElMaestro 2013-08-14 11:29
- TRT|RTR rulez? Really?d_labes 2013-08-14 08:16
- TRT|RTR rulez! Helmut 2013-08-13 18:23
- 3-per, 2-trt designs and estimation of intra-subj. variance ElMaestro 2013-08-13 15:00
- 3-per, 2-trt designs and estimation of intra-subj. variance Dr_Dan 2013-08-13 10:11
Ing. Helmut Schütz