Special line graph

[Michael Massaro]

Hello,

I think I have a very simple question, but I can't find the answer.

I have a dataset and I created a dummy.

I'd like to plot the mean of the dummy over the years.

I manage to do that with

graph bar (mean) dummy, over(year)

But I'd like to see the trend line instead of the bar chart. How can I do that?

Corollary question: what if I'd like to plot two trends as the above in the same graph, i.e. what I now see typing graph bar (mean) dummy1, over(year) and graph bar (mean) dummy2, over(year) but as two lines in the same graph?

Thanks!

[Nick Cox]

You need to switch to twoway.

forval j = 1/2 { 
     egen mean`j' = mean(dummy`j'), by(year)
} 

twoway line mean? year, sort

That's not a trend line (how do you define that? linear? quadratic? local polynomial? cubic spline?) but it's a basic line graph.