Using rdrobust to calculate 2sls and getting error message stating "should be set within the range of x" - statistics

Question

I am trying to calculate a two stage least squares in Stata. My dataset looks like the following:
income bmi health_index asian black q_o_l age aide
100 19 99 1 0 87 23 1
0 21 87 1 0 76 29 0
1002 23 56 0 1 12 47 1
2200 24 67 1 0 73 43 0
2076 21 78 1 0 12 73 1
I am trying to use rdrobust to estimate the treatment effect. I used the following code:
rdrobust q_o_l aide health_index bmi income asian black age, c(10)
I varied the income variable with multiple polynomial forms and used multiple bandwidths. I keep getting the same error message stating:
c() should be set within the range of aide
I am assuming that this has to do with the bandwidth. How can I correct it?

Answer 1

You have two issues with the syntax. You wrote:
rdrobust q_o_l aide health_index bmi income asian black age, c(10)
This will ignore health_index-age variables, since you can only have one running variable. It will then try to use a cutoff of 10 for aide (the second variable is always the running one). Since aide is binary, Stata complains.
It's not obvious to me what makes sense in your setting, but here's an example demonstrating the problem and the two remedies:
. use "http://fmwww.bc.edu/repec/bocode/r/rdrobust_senate.dta", clear
. rdrobust vote margin, c(0) covs(state year class termshouse termssenate population)
Covariate-adjusted sharp RD estimates using local polynomial regression.
Cutoff c = 0 | Left of c Right of c Number of obs = 1108
-------------------+---------------------- BW type = mserd
Number of obs | 491 617 Kernel = Triangular
Eff. Number of obs | 309 279 VCE method = NN
Order est. (p) | 1 1
Order bias (q) | 2 2
BW est. (h) | 17.669 17.669
BW bias (b) | 28.587 28.587
rho (h/b) | 0.618 0.618
Outcome: vote. Running variable: margin.
--------------------------------------------------------------------------------
Method | Coef. Std. Err. z P>|z| [95% Conf. Interval]
-------------------+------------------------------------------------------------
Conventional | 6.8862 1.3971 4.9291 0.000 4.14804 9.62438
Robust | - - 4.2540 0.000 3.78697 10.258
--------------------------------------------------------------------------------
Covariate-adjusted estimates. Additional covariates included: 6
. sum margin
Variable | Obs Mean Std. dev. Min Max
-------------+---------------------------------------------------------
margin | 1,390 7.171159 34.32488 -100 100
. rdrobust vote margin state year class termshouse termssenate population, c(7) // margin rang
> es from -100 to 100
Sharp RD estimates using local polynomial regression.
Cutoff c = 7 | Left of c Right of c Number of obs = 1297
-------------------+---------------------- BW type = mserd
Number of obs | 744 553 Kernel = Triangular
Eff. Number of obs | 334 215 VCE method = NN
Order est. (p) | 1 1
Order bias (q) | 2 2
BW est. (h) | 14.423 14.423
BW bias (b) | 24.252 24.252
rho (h/b) | 0.595 0.595
Outcome: vote. Running variable: margin.
--------------------------------------------------------------------------------
Method | Coef. Std. Err. z P>|z| [95% Conf. Interval]
-------------------+------------------------------------------------------------
Conventional | .1531 1.7487 0.0875 0.930 -3.27434 3.58053
Robust | - - -0.0718 0.943 -4.25518 3.95464
--------------------------------------------------------------------------------
. rdrobust vote margin state year class termshouse termssenate population, c(-100) // nonsensical
> cutoff for margin
c() should be set within the range of margin
r(125);
end of do-file
r(125);
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