Adding confidence intervals to a two-way line graph

[Aline Trautmann]

Dear all,

I think this an easy question but I got stuck.

For a seminal replication study, I would like to plot a line graph showing the means of my variable of interest and combine this with the confidence intervals.
I can use ciplot, ci and statsby, but I am quite uncommon with both latter commands.
I also found the option of adding a rcap graph, but I haven't figured out, how to compute the high and low values the confidence level (95%) of each observation (mean) of my variable in time as I am working with panel data.

The code is the following:

 // Figure 3
by syear T1, sort: egen meannoabs = mean(leadnoabs)
* without rap
twoway (line meannoabs syear if T1 == 1 & syear!=1996) (line meannoabs syear if T1 == 0 & syear!=1996) , legend(order(1 "Treatment" 2 "Control")) scheme(sj) name(graph3a, replace)

gen hi = meannoabs+1.96*se(meannoabs)
gen lo = meannoabs-1.96*se(meannoabs)

* just rcap CI
twoway (rcap meannoabs hi lo if T1==1) (rcap meannoabs hi lo if T1==0)

* combined 
twoway (line meannoabs syear if T1 == 1 & syear!=1996) (line meannoabs syear if T1 == 0 & syear!=1996) (rcap meannoabs hi lo if T1==1) (rcap meannoabs hi lo if T1==0), legend(order(1 "Treatment" 2 "Control")) scheme(sj) 

*graph export

T1 is the treatment dummy (0 = control, 1=treated). I know that ciplot stores upper and lower values as scalars. My main problem is working with panel data, as I need for every year the CI...

I am using Stata 15.1

Thank you very much in advance.

Aline

[Marcos Almeida]

Try something like:

 twoway (line meannoabs syear) (rcap lo hi syear)