st: RE: Drop under several conditions and time (year)

[Joe Canner <jcanner1@jhmi.edu>]

Did you try Nick's suggestion in response to your last post?
________________________________________
From: owner-statalist@hsphsun2.harvard.edu [owner-statalist@hsphsun2.harvard.edu] on behalf of Julian Kochan [julian.kochan@gmx.de]
Sent: Sunday, March 23, 2014 4:10 PM
To: statalist@hsphsun2.harvard.edu
Subject: st: Drop under several conditions and time (year)

Hi,

i have a set of data with financial firm characteristics of about 10.000 firms for Year 2000 - Year 2012.

Let's assume: The first column of the data table displays the Name of the firm, the second the Year, the third displays the LongTerm Debt and the fourth the TotalAssets.
Thus, 13 rows in a row (2000-2012) display information about just one firm - just the year varies.

Problem: I want to drop those firms, for which LongTermDebt is greater than TotalAssets in the Year 2007 or Year 2008.
                 If this is the case, the firm should be dropped out of my data completely such that the firm observation is not only dropped for 2007 and 2008, but also for all the other years.

                I tried: drop if Year == 2007 | Year == 2008 & LongTermDebt > TotalAssets. This made Stata to delete about 5000 observation altough I just had 150 observations with LongTermDebt > Total Assets.
                There is something I do not get as a Stata beginner. Is the drop function the wrong function when trying to delete observations under several conditions such as comparing Debt to Assets ?

I would be really really happy to receive an answer.

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

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