Hi all,
I am researching on consumers’ WTP for woods sourced from different sources. I wanted to generate an efficient design for three unlabelled alternatives with an opt-out. However, the design could NOT be generated. I appreciate if anyone gives me a hand.
Here is the code
Design
;alts = alt1*,alt2*,alt3*,alt4
;rows = 36
;block = 6
;eff = (mnl,d,median)
;rdraws=halton(5000)
;bdraws=halton(5000)
;model:
U(alt1) = b1.effects[(n,0.1,0.05)| (n,0.09,.05)|0]*SFWA[3,2,1,0] + b2.effects[(n,0.1,0.03)|0]*LOGOA[2,1,0] +b3[(n,-0.08,0.01)]*DFWA[50,100,200, 300] + b4[(n,-0.02,0.01)]*COSTA[220,240,260, 280]/
U(alt2) =b1*SFWA+b2*LOGOA+b3*DFWA+b4*COSTA/
U(alt3) = b1*SFWA+b2*LOGOA+b3*DFWA+b4*COSTA/
U(alt4) = b5(0.1)$
Thanks in advance