qreg- error message

[Masoumeh Sanagou]

Hi STATALIST,

I used the following command:

set seed 1001
sqreg A b1.B, quantile(.25 .5 .75)

and I got this error message:

 quantile:  0 coefs estimated
.75 quantile:  1coefs estimated
same model cannot be used to estimate both quantiles; sample size probably too small
r(498);

Is there any advice on how to solve this problem?

I have around 86,430 data. Using randomtag, this is a sample of the data:

* Example generated by -dataex-. For more info, type help dataex
clear
input double A float B
           5.65032e-09 1
5.6769199999999995e-09 1
          1.628849e-08 1
1.2521000000000003e-10 2
          1.746179e-08 2
             1.165e-10 2
           8.77735e-09 2
            1.1475e-10 2
           8.76799e-09 2
          6.829762e-08 3
          1.670037e-08 3
1.5580500000000002e-08 3
            1.0653e-10 3
            1.1757e-10 3
          2.562106e-08 3
1.2002000000000002e-10 3
1.1449000000000001e-10 3
            1.0886e-10 3
1.0947999999999999e-10 3
 7.767400000000001e-09 4
          1.235895e-08 4
1.7939089999999998e-08 4
 9.440100000000001e-09 4
          1.567156e-08 4
1.1825856999999999e-07 4
          1.244867e-08 4
          1.106799e-08 4
1.1050970000000001e-08 5
            1.1264e-10 5
           8.88932e-09 5
end
label values B B
label def  B 1 "1st six minutes", modify
label def  B 2 "2nd six minutes", modify
label def  B 3 "3rd six minutes", modify
label def  B 4 "4th six minutes", modify
label def  B 5 "5th six minutes", modify

P.S.
the following work well:

set seed 1001
sqreg A b1.B, quantile(.25)
set seed 1001
sqreg A b1.B, quantile(.5)
set seed 1001
sqreg A b1.B, quantile( .75)
set seed 1001
sqreg A b1.B, quantile(.25 .5)

but the same error message for these:

set seed 1001
sqreg A b1.B, quantile(.25 .75)
set seed 1001
sqreg A b1.B, quantile(.5 .75)

Regards,