confirm syntax of continuous variables in efficient designs
Posted: Thu Nov 14, 2019 4:32 pmDear Ngene expert:
Thank you very much for your previous reply.
This is my revised syntax:
Design
;alts=alt1*,alt2*,alt3
;rows=24
;block=4
;eff=(mnl,d)
;model:
U(alt1)=b1.effects[0.001]*A[1,0]+b2.effects[0.003|0.002|0.001]*B[3,2,1,0]+b3.effects[0.001|0.001|0.001]*C[3,2,1,0]+b4[0.001]*D[0,20,40,60]+b5[-0.001]*E[100,250,400,550]/
U(alt2)=b1*A+b2*B+b3*C+b4*D+b5*E/
U(alt3)=b0[0]
$
My variable D and variable E are continuous variables. According to your previous suggestions, I use the actual attribute level to represent my continuous variables, that is, for attribute D, 0 represents 0 yuan, 20 represents 20 yuan, 40 represents 40 yuan, and 60 represents 60 yuan. And for attribute E, 100 means 100 yuan, 250 means 250 yuan, 400 means 400 yuan, 550 means 550 yuan.
And my question is:
1.As shown above, My attribute A,B,C use the virtual attribute levels, but attribute D,E use the actual attribute levels. Is there any problem? Will this affect the efficiency of the design?
2.And in the end, I want to ask, is there any problem with my syntax as a whole?
I’m more thankful than I can express. Best wishes for you.
Thank you very much for your previous reply.
This is my revised syntax:
Design
;alts=alt1*,alt2*,alt3
;rows=24
;block=4
;eff=(mnl,d)
;model:
U(alt1)=b1.effects[0.001]*A[1,0]+b2.effects[0.003|0.002|0.001]*B[3,2,1,0]+b3.effects[0.001|0.001|0.001]*C[3,2,1,0]+b4[0.001]*D[0,20,40,60]+b5[-0.001]*E[100,250,400,550]/
U(alt2)=b1*A+b2*B+b3*C+b4*D+b5*E/
U(alt3)=b0[0]
$
My variable D and variable E are continuous variables. According to your previous suggestions, I use the actual attribute level to represent my continuous variables, that is, for attribute D, 0 represents 0 yuan, 20 represents 20 yuan, 40 represents 40 yuan, and 60 represents 60 yuan. And for attribute E, 100 means 100 yuan, 250 means 250 yuan, 400 means 400 yuan, 550 means 550 yuan.
And my question is:
1.As shown above, My attribute A,B,C use the virtual attribute levels, but attribute D,E use the actual attribute levels. Is there any problem? Will this affect the efficiency of the design?
2.And in the end, I want to ask, is there any problem with my syntax as a whole?
I’m more thankful than I can express. Best wishes for you.