Stata The Stata listserver
[Date Prev][Date Next][Thread Prev][Thread Next][Date index][Thread index]

st: Collapsing with strings

From   Marcello Pagano <>
Subject   st: Collapsing with strings
Date   Fri, 13 Jan 2006 13:30:07 -0500

For Daphna Bassok:


I am having a frustrating problem and would love some advice.

I have several duplicate observations in my data set. However, they are not perfect duplicates. Only the id # is the same. So there might be two observations with id#16 for instance, the first will have values for some variables, and missing values for others. The second also have some values filled and some missing. There are no cases in which both have values- that is... either the first in the pair has the value OR the second has a value (or neither).

For example: suppose I have two observations with id# 16... The first has values for var1 and 2 and not 3. The second ONLY has values for var 3. What i would like to do is simply collapse these into a single observation with all the relevant info. meaning, 1 observation with id#16 that has values for all three variables.

I am trying to do this with the collapse command with no success.

My code is:

collapse (min) var1-var3, by(id)

I thought this would create a new observation that has all the data in it.

I am getting a "type mismatch" error.

Is this because some of my variables are string variables?

How can i get around this?

Thanks in advance for your help,

* For searches and help try:

© Copyright 1996–2021 StataCorp LLC   |   Terms of use   |   Privacy   |   Contact us   |   What's new   |   Site index