mixlogitwtp: Variable has no within-group variance

[Kotryna Klizentyte]

I have estimated my discrete choice experiment with 'mixlogitwtp' and it ran perfectly:

. mixlogitwtp choice rec_some rec_all eh_high wq_inc ei_pos, group(setid) price(mtax)

Iteration 0: log likelihood = -10467.376
Iteration 1: log likelihood = -10466.948
Iteration 2: log likelihood = -10466.703
Iteration 3: log likelihood = -10466.689
Iteration 4: log likelihood = -10466.688

Mixed logit model in WTP space Number of obs = 29,220
Wald chi2(6) = 3667.42
Log likelihood = -10466.688 Prob > chi2 = 0.0000

------------------------------------------------------------------------------
choice | Coef. Std. Err. z P>|z| [95% Conf. Interval]
-------------+----------------------------------------------------------------
Mean |
rec_some | 27.50139 7.621863 3.61 0.000 12.56281 42.43996
rec_all | 85.18586 8.760342 9.72 0.000 68.0159 102.3558
eh_high | 76.64796 8.281869 9.25 0.000 60.4158 92.88013
wq_inc | 92.22739 9.187993 10.04 0.000 74.21926 110.2355
ei_pos | 139.1418 10.5668 13.17 0.000 118.4312 159.8523
mtax | -5.639376 .0974011 -57.90 0.000 -5.830279 -5.448474
-------------+----------------------------------------------------------------
SD |
mtax | -.3066658 .2728991 -1.12 0.261 -.8415383 .2282067
------------------------------------------------------------------------------
The sign of the estimated standard deviations is irrelevant: interpret them as
being positive


When I am including my demographic variables that are dummy coded (0/1) I receive this error for every single variable: Variable 'x' has no within-group variance

Here is an example of my dataset (there are 27,000 observations):

id	choiceset	block	alt	optionA	optionB	optionC	choice	tax	Rec_None	Rec_Some	Rec_All	EH_High	EH_Low	WQ_Inc	WQ_Dec	EI_Pos	EI_Neg	setid	Gender.Female	Age	Resident.FL	Income20	income40	income60	income80	income100	income100P	Race	White	African.Am	Hispanic	AI	Asian.Am	NH
1	1	3	1	1	0	0	0	100	0	0	1	0	1	0	1	0	1	1	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	1	3	2	0	1	0	1	150	0	1	0	1	0	1	0	0	1	1	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	1	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	1	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	2	3	1	1	0	0	1	100	0	0	1	1	0	1	0	1	0	2	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	2	3	2	0	1	0	0	50	1	0	0	1	0	0	1	1	0	2	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	2	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	2	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	3	3	1	1	0	0	0	200	1	0	0	1	0	0	1	1	0	3	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	3	3	2	0	1	0	0	100	0	1	0	0	1	0	1	1	0	3	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	3	3	3	0	0	1	1	0	0	0	0	0	0	0	0	0	0	3	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	4	3	1	1	0	0	0	150	0	1	0	0	1	0	1	0	1	4	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	4	3	2	0	1	0	0	200	1	0	0	1	0	0	1	1	0	4	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
1	4	3	3	0	0	1	1	0	0	0	0	0	0	0	0	0	0	4	0	31	1	1	0	0	0	0	0	2	0	1	0	0	0	0
2	1	3	1	1	0	0	0	100	0	0	1	0	1	0	1	0	1	5	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	1	3	2	0	1	0	1	150	0	1	0	1	0	1	0	0	1	5	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	1	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	5	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	2	3	1	1	0	0	1	100	0	0	1	1	0	1	0	1	0	6	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	2	3	2	0	1	0	0	50	1	0	0	1	0	0	1	1	0	6	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	2	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	6	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	3	3	1	1	0	0	1	200	1	0	0	1	0	0	1	1	0	7	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	3	3	2	0	1	0	0	100	0	1	0	0	1	0	1	1	0	7	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	3	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	7	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	4	3	1	1	0	0	0	150	0	1	0	0	1	0	1	0	1	8	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	4	3	2	0	1	0	1	200	1	0	0	1	0	0	1	1	0	8	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
2	4	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	8	1	39	1	1	0	0	0	0	0	1	1	0	0	0	0	0
3	1	3	1	1	0	0	0	100	0	0	1	0	1	0	1	0	1	9	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	1	3	2	0	1	0	1	150	0	1	0	1	0	1	0	0	1	9	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	1	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	9	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	2	3	1	1	0	0	0	100	0	0	1	1	0	1	0	1	0	10	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	2	3	2	0	1	0	1	50	1	0	0	1	0	0	1	1	0	10	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	2	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	10	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	3	3	1	1	0	0	0	200	1	0	0	1	0	0	1	1	0	11	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	3	3	2	0	1	0	1	100	0	1	0	0	1	0	1	1	0	11	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	3	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	11	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	4	3	1	1	0	0	1	150	0	1	0	0	1	0	1	0	1	12	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	4	3	2	0	1	0	0	200	1	0	0	1	0	0	1	1	0	12	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0
3	4	3	3	0	0	1	0	0	0	0	0	0	0	0	0	0	0	12	1	44	0	0	0	1	0	0	0	1	1	0	0	0	0	0