I like Phil Schumm's solution but wanted to see if I could come up with a way to identify the second largest. As primitive as it is, this seems to work:
. egen max = rmax(votesa-votesd)
. foreach var of varlist votesa votesb votesc votesd {
2. replace `var' = . if `var' == max
3. }
(0 real changes made)
(1 real change made, 1 to missing)
(0 real changes made)
(4 real changes made, 4 to missing)
. egen second = rmax(votesa-votesd)
. gen mofv = max - second
. l
+-----------------------------------------------------------------+
| state votesa votesb votesc votesd max second mofv |
|-----------------------------------------------------------------|
1. | 1 10 1 6 . 21 10 11 |
2. | 2 11 2 7 . 22 11 11 |
3. | 3 12 3 8 . 13 12 1 |
4. | 4 1 . 2 3 4 3 1 |
5. | 5 2 5 3 . 7 5 2 |
+-----------------------------------------------------------------+
You may have a problem with ties but you didn't specify how you wanted to handle any such eventuality.
Best wishes,
Eric
>i have the following problem:
>
>i want to construct a variable called margin of victory:
>
>my data set looks something like this:
>
>
>state votesA votesB votesC votesD
>1 10 1 6 21
>2 11 2 7 22
>3 12 3 8 13
>4 1 4 2 3
>5 2 5 3 7
>
>
>my question is:
>
>how do i create a variable called margin_of_victory = votes for 1st place - votes for 2nd place?, i.e. 21-10 for state 1, 22 - 11 for state 2, 13 - 12 for state 3, 4 - 3 for state 4, etc.
>
>i can't do this by hand, since i have a huge data set.
>
>i know that the command
>
>. egen margin_of_victory = rmax (votesforA votesforB votesforC votesforD)
>
>
>will help me pick the biggest number in each row, but how do i get to choose the 2nd biggest number?
>
>thanks many, and sorry if this is a silly question.
>
>thanks many.
>
>ISB
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