st: RE: AW: RE: line plot

["Nick Cox" <n.j.cox@durham.ac.uk>]

-collapse- as mentioned by Martin Weiss is fine too. The difference is
that after -collapse- you need to retrieve your original dataset to do
further analyses with it in the same session. 

Nick 
n.j.cox@durham.ac.uk 

Mareike

Thank you Nick for your help. Using egen first solved the problem.

Nick Cox

There is a difference of principle here. 

-graph bar-, -graph dot- and -graph box- are reduction commands that
typically show summary statistics derived from the data, rather the data
themselves. (There are exceptions, flagged by -asis-.)

On the other hand, most -twoway- commands, and those based on them, how
the data directly. (There are exceptions, such as -histogram-.) Thus,
for the most part, you need to do any reductions beforehand. 

Use -egen, total()- to calculate the sums beforehand. Note also -egen,
tag()- to tag just one observation of each kind, in your case, one
observation for each year. 

Mareike

I'm working with panel data and I'm trying to plot the yearly sum of 
one variable for all countries over time. I was able to create a bar 
diagram for that purpose by using the command: graph bar (sum) 
variable, over(year). But actually I would prefer to present the 
numbers in form of a line plot: But all the commands I could think of 
(e.g. tsline, line, twoway connected, etc.) do not allow the 
sum-option, as far as I understand them correctly. It would be great if 
anybody of you would get up with an idea!?

*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/