218
edits
Changes
Jump to navigation
Jump to search
==SQL merges==
See documentation in <code>E:\McNair\Projects\LBO\Clean\LBO Innovation SQL Script.txt</code>
Basic outline is as follows:
*Imported COMPUSTAT Data
**Built composite primary key from unique gvkeys cross-producted with years 1970 to 2015 (all other datasets will be joined onto this)
**Stripped out list of unique company names from COMPUSTAT data
**Used matcher to construct standardized company names, with lookup table to original names
**Joined gvkeys back into lookup table
*Imported Brian's hand-cleaned SDC data on LBOs
**Sheet 1 contains main list of LBOs
**Sheet 2 contains gvkey to dealnumb link
**Sheet 3 contains COMPUSTAT output (unused)
**Sheet 4 contains private-to-private LBOs
*Use SDC data to flag LBO events for COMPUSTAT data
**Joined sheets 1 and 2 to link gvkey to each LBO deal
**Joined resulting table to composite key to flag for LBO occurrences in given year-gvkey combination
==STATA analysis==
The Effect of Leverage Buyouts on Innovation (view source)
Revision as of 16:33, 3 November 2016
, 16:33, 3 November 2016→New Version
*'''''LBOsheet2:''''' Second sheet of Brian's data; used to construct gvkey-to-dealnumb link
*'''''yearsbygvkeys:''''' Composite primary key (all years 1970 to 2015 cross-producted with unique gvkeys); all other data is joined onto this
==Construction of Dataset==
==SQL merges==
See documentation in <code>E:\McNair\Projects\LBO\Clean\LBO Innovation SQL Script.txt</code>
Basic outline is as follows:
*Imported COMPUSTAT Data
**Built composite primary key from unique gvkeys cross-producted with years 1970 to 2015 (all other datasets will be joined onto this)
**Stripped out list of unique company names from COMPUSTAT data
**Used matcher to construct standardized company names, with lookup table to original names
**Joined gvkeys back into lookup table
*Imported Brian's hand-cleaned SDC data on LBOs
**Sheet 1 contains main list of LBOs
**Sheet 2 contains gvkey to dealnumb link
**Sheet 3 contains COMPUSTAT output (unused)
**Sheet 4 contains private-to-private LBOs
*Use SDC data to flag LBO events for COMPUSTAT data
**Joined sheets 1 and 2 to link gvkey to each LBO deal
**Joined resulting table to composite key to flag for LBO occurrences in given year-gvkey combination
==STATA analysis==
==Data Pulls==
*Brian Ayash's hand-cleaned list of LBOs (with gvkeys). This exists as the list_and_data.xlsx table.
*List of failed LBOs. This exists as the failedLBOs2.xlsx table.
=Old Version=
