Get overview of my (unbalanced) panel data

[Dominic Berg]

Hello everyone,

I have to say at first that I'm far from being a Stata expert, but I have to use it for my master's thesis and I hope you can help me.

So I have panel data from four different sources in total and I managed to merge them together, but the data set is unbalanced; the data sources neither cover all the same years nor all the same countries, but of course they overlap to great extend. Is there a command to get an overview for every country (id) for which timespan (year) my explanatory variables are available and drop specific countries and years afterwards to get a balanced panel?

And a second question where I don't know whether I should open a seperate thread for it: When I use the command

xtsum id year var1 var2 etc.

there is no within variation (standard deviation) in countries, but some between variation in years. I thought that shouldn't exist? Or does it have to do with the unbalanced data? What do I do about it?

Help would be highly appreciated! Btw of course I googled before asking, but didn't find anything that helped me. If there is more information you need, please tell me. Thank you in advance.

[Nick Cox]

You don't say how many countries or how many years, which will affect what is easy and not so easy to think about. You could just go

scatter id year

Let's suppose that there are 30 countries. Then something like

scatter id year, yla(1/30, valuelabel ang(h))

might work better. If your value is not 30, then revise accordingly. Then something like

scatter id year if !missing(whatever), yla(1/30, valuelabel ang(h))

is a way to see where and when there are non-missing values for whatever.