### which is the prior for b0 in U(alt3)

Posted:

**Fri Dec 06, 2019 12:52 pm**Dear Ngene Experts,

Here is our code for DCE pilot design. After piloting, we analyzed the pilot data and used asclogit in Stata to analyze the pilot data. The stata result is as follows. The question is for the formal design, which is the prior from Stata asclogit result should be used for b0 in U(alt3)?

Design

;alts=alt1*,alt2*,alt3

;rows=24

;block=4

;eff=(mnl,d)

;model:

U(alt1)=b1.effects[0.001]*A[1,0]+b2[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]

$

The stata result(coef):

Alt : b1:.3790657

b2:.0002358

b3 :.0411187; 0.1913767; 0.1317095

b4 :.0083367

b5 :.0017246

1 cons: 2.490288

2 cons: 2.40686

3: (base alternative)

Thank you very much!

Here is our code for DCE pilot design. After piloting, we analyzed the pilot data and used asclogit in Stata to analyze the pilot data. The stata result is as follows. The question is for the formal design, which is the prior from Stata asclogit result should be used for b0 in U(alt3)?

Design

;alts=alt1*,alt2*,alt3

;rows=24

;block=4

;eff=(mnl,d)

;model:

U(alt1)=b1.effects[0.001]*A[1,0]+b2[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]

$

The stata result(coef):

Alt : b1:.3790657

b2:.0002358

b3 :.0411187; 0.1913767; 0.1317095

b4 :.0083367

b5 :.0017246

1 cons: 2.490288

2 cons: 2.40686

3: (base alternative)

Thank you very much!