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Hi Michiel,

I'm creating an explicit and implicit partial profiles design for the first time and have a couple of questions. Of the ten attributes in my design, six are dummy-coded side effects (presence/absence) attributes, the rest are effectiveness and mode of administration attributes ...

Hi Michiel,

Thank you so much for the speedy response. Both of your suggestions worked perfectly!

Thank you ever so much for your help.
Tara

Hi Michiel,

I am having difficulty generating a design in Ngene using the following code. The issue seems to stem from correlation within the "advtreatment" attribute, resulting in undefined output.

design
;alts = surgery*, medication*
;rows=60
;block=6
;eff=(mnl,d)
;alg=mfederov
;reject ...

Thanks Michiel that resolved the collinearity issue - it's great to finally find a solution! Also, thanks for your feedback about the attributes, complications is a compound attribute with corresponding risks, sorry I forgot to include them in the ngene annotations.

Hi Michiel,

I estimated a model with some pre-testing data for the Ngene code you helped me with and have a follow up question. When I code the wait time attribute as a categorical variable, the level 24 weeks is omitted because of collinearity. However, the model runs fine when I code the wait ...

Thank you for your helpful suggestions!! I really appreciate your help.

Tara

Thanks Michiel!! That worked for wait but have a follow-up question about discomfort which is dummy coded.

I get an error message: "Error: An attribute has the wrong number of levels for dummy or effects coding. 'discomfort2'."
Is the solution to include all three levels (minimal, moderate, high ...

Hi Michiel,

I'm attempting a labelled designs and have come across this error message: "Error: Two identically named attributes do not have consistently specified levels: 'bloodtest.wait', 'endoscopy.wait'"
Ideally, i would like to have the same coefficient for waiting time in both endoscopy and ...

Thank you so much for your advice!

Tara

Dear Michiel,

After doing a small pilot study, I would like to change a level of one of my attributes. The attribute was coded as a linear variable:

b1[0.00001] * frequency[1,2,4,6]

I would like to remove 6 weeks and instead add 3 weeks. Can I swap 6 weeks for 3 weeks? If I had coded this as a ...