Dataset:
128 000 merger bids between 01/01/1980 and 31/12/2020.
Relevant variables:
Announcement date (dd/mm/yyyy)
Acquiror ID (6-digit number)
Target ID (6-digit number)
Each acquiror and target can appear multiple times (as an acquiror can acquire multiple targets and there can be multiple acquirors bidding on a target).
I have created a subset of targets that are subject to bidding competition, meaning targets that appear multiple times with different acquirors.
I now want to subset this sample into first-bidders and followers.
First-bidder: announcement date before other bids for the same target
Follower: announcement date after first bid for the same target
Preferably, acquirors should be grouped so that bids for a target are no more than 12 months apart. If not, there might not actually be competition as a target could be acquired by one firm and then acquired by another years late.
I'm looking for help on how to program the first-bidder vs. follower subsetting.
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