Unbalanced panel descriptives

[Rachel Sleeps]

Hi,
I am interested in better understanding how to get useful descriptive statistics for my unbalanced panel with Stata 13. I have panel data with abourt 13.000 observations and about 4000 objects over 12 years. I would like to know:

1. the number of consecutive observations per object
2. the average number of consective observations
3. the longest spell / best spell to use

I was told that

tsspell

could help me out. But I can't find it on the SSC... Is there any other way to get a hold of this information?

I am relatively new to Stata (I am used to R) and I am sure this is a very beginners question. But I can't get a hold of it.

Thank you very much
/R

[Joseph Coveney]

Typing

search tsspell

in Stata brings up a Viewer window that contains a hyperlink to it on SSC. The hyperlink is

net describe tsspell, from(http://fmwww.bc.edu/RePEc/bocode/t)

and so you could copy and paste that into your Stata command line to go directly there.

[Rachel Sleeps]

Thanks! It worked now with net install! But, does tsspell help me obtaining the information I seek?

[Nick Cox]

Did you read the help?

 
ssc inst tsspell 
help tsspell

1. Spells of consecutive observations: This is an example in the help.

2. The average number of consecutive observations. You need to be precise here. This panel contains 5 consecutive observations by one definition, as there are 2 spells that contain consecutive observations. Do you mean of the longest spell?

 
id     time 
42     1
42     2
42     3
42     11
42     12

3a. Longest spell. This follows immediately from a close reading of the help. The length of the longest spell for each panel is

 
egen length_longest = max(_seq), by(id)

The longest spell itself is identifiable by

 
bysort id (_seq) : gen which_longest = _spell

except that you need a rule for dealing with ties.


3b, Best spell. Not defined.

See also http://www.stata-journal.com/sjpdf.h...iclenum=dm0029 for a discussion of principles.

[Rachel Sleeps]

Perfect! Thank you. The help function is great, really. Now I know better and will check it first!