I hope this is not too trivial question (I have search the manual and the forum and could not find the answer)
I am trying to create a very simple generic orthogonal design with 3 alts, each is described by the same 3 atts, each att has the same 3(ordinal categorical) levels.
this is the code:
- Code: Select all
Design
;alts = alt1, alt2, alt3
;rows = 12
;orth = sim
;model:
U(alt1) = b1 [0.00001]* A[1,2,3] + b2[0.00001]* B[1,2,3] + b3 [0.00001]* C[1,2,3] /
U(alt2) = b1 * A+ b2 * B + b3*C/
U(alt3)= b1 * A+ b2 * B + b3*C$
I don't have priors, yet all the atts. are positive ones, so I assigned very small positive prior values.
The problem is that some scenarios includes dominant (or inferior) alternatives that can yield no info.
for example:
Scenario 3
alt1 alt2 alt3
a 3 1 1
b 3 2 2
c 3 1 3
I have also tried the option ;orth = ood, yet the problem remains.
How can I avoid these situations?
Any help on this will be highly appreciated!