Dear Statalist:

*First, I run the following Modified Pearson Regression with interactions

glm k6cat Cancer##caregiving i.sex_cat ib0.age_cat ib0.edu i.job i.setaiexpbyninsu_cat ib1.smoking Diabetes Eye_disease Hypertension Stroke Myocardial_infarction Asthma Gastroduodenal_dis Disease_of_liver_bowel Rheumatoid_arthritis Arthropathy Lower_back_pain Osteoporosis Fracture, fam(Poisson) link(log) nolog eform vce(robust) allbaselevels

The main variables are defined as:
- k6 cat: binary. Cancer2 (binary, 0=no cancer, 1= cancer), caregiving2 (binary, 0= not caregiving, 1= caregiving)


Generalized linear models Number of obs = 672,849
Optimization : ML Residual df = 672,823
Scale parameter = 1
Deviance = 462649.7608 (1/df) Deviance = .6876248
Pearson = 493030.1896 (1/df) Pearson = .7327784

Variance function: V(u) = u [Poisson]
Link function : g(u) = ln(u) [Log]

AIC = 1.218347
Log pseudolikelihood = -409855.8804 BIC = -8566148

---------------------------------------------------------------------------------------------
| Robust
k6cat | IRR Std. Err. z P>|z| [95% Conf. Interval]
----------------------------+----------------------------------------------------------------
Cancer2 |
0 | 1 (base)
1 | 1.467965 .0191241 29.47 0.000 1.430957 1.50593
|
caregiving2 |
0 | 1 (base)
1 | 1.297198 .0212495 15.88 0.000 1.256211 1.339522
|
Cancer2#caregiving2 |
0 0 | 1 (base)
0 1 | 1 (base)
1 0 | 1 (base)
1 1 | .9320186 .0878053 -0.75 0.455 .7748775 1.121027
|


* Second, I run: test 1.Cancer#0.caregiving=0.Cancer#1.caregiving
It showed the following:

test 1.Cancer2#0.caregiving2=0.Cancer2#1.caregiving2

( 1) - [k6cat]0b.Cancer2#1o.caregiving2 + [k6cat]1o.Cancer2#0b.caregiving2 = 0
Constraint 1 dropped

chi2( 0) = .
Prob > chi2 = .


* Third, the Constraint dropped giving me empty values. Then I tried to test the constraints (only to wanting to knnow where the error is), and I found:

test 1.Cancer2 0.caregiving2 0.Cancer2 1.caregiving2

( 1) [k6cat]1.Cancer2 = 0
( 2) [k6cat]0b.caregiving2 = 0
( 3) [k6cat]0b.Cancer2 = 0
( 4) [k6cat]1.caregiving2 = 0
Constraint 2 dropped
Constraint 3 dropped

chi2( 2) = 1099.42
Prob > chi2 = 0.0000

It seems that 0.Cancer2 and 0.caregiving2 have "an error" which I can't recognize.

Please, can you help me with this. Thank you in advance