Variable indicating whether an outcome has happened

[Magne Hagesater]

Hi list,

I'm stuggling to create some indicator variables and wondering if anyone can help me on this.

I have a event based data set showing outcomes of an event occuring in countries and years. I want to create a variable indicating whether a particular outcome has previously occured in a country. In addition, I would like to create another variable showing the amount of years since the outcome last occured in each country.

I'm grateful for all advises.

Best regards,
Magne

[Nick Cox]

If you have an indicator that is 1 in an event year and 0 otherwise, then the number of events to date is just the cumulative sum of that indicator within panels; and an indicator for "has previously happened" can be calculated from that cumulative sum (or its previous value).

The time since the last event is just (current date - date of last event), so you must carry forward the date of the last event..

webuse grunfeld, clear 
gen event = invest > 400 
gen last = year if event 
bysort company (year) : replace last = last[_n-1] if missing(last) 
by company : gen happened = sum(event) 
gen time_since = year - last 
edit

[Magne Hagesater]

Perfect. Thank you very much for the quick reply.

[Steve Samuels]

I'll just add that if you read the Statalist Advice, http://www.statalist.org/forums/help#gfaq_postingadvice, you will see the request to use full real names. Please do so in future posts.