Stata: Reverse Sort

Question

I have a data set that looks like this:

id varA  varB   varC
1   0     10    .
1   0     20    .
1   0     35    .
2   1     60    76
2   1     76    60 
2   0     32    .

I want to create the varC that reverses the order of varB only for the values varA=1 and missing otherwise.

Is this really reverse sorting, or is it a matter of giving pairs of observations the other observation's values? See stata-journal.com/article.html?article=dm0043 — Nick Cox
– Nick Cox, Commented Feb 19, 2021 at 17:12
Thank you for your answer Nick. I believe that this document applies to the cases when we already have another variable that defines the pairing i.e. VarC in this case. However, I don't have the varC and I want to create it based on varB. — adamsalenushka
– adamsalenushka, Commented Feb 21, 2021 at 18:49

Nick Cox · Accepted Answer · 2021-02-21 21:49:30Z

1

This may help:

clear 
input id varA  varB   varC
1   0     10    .
1   0     20    .
1   0     35    .
2   1     60    76
2   1     76    60 
2   0     32    .
end 

gen group = sum(id != id[_n-1] | varA != varA[_n-1])
sort group, stable 
by group: gen wanted = cond(varA == 1, varB[_N - _n + 1], .)

list id var* wanted, sepby(id varA) 

     +----------------------------------+
     | id   varA   varB   varC   wanted |
     |----------------------------------|
  1. |  1      0     10      .        . |
  2. |  1      0     20      .        . |
  3. |  1      0     35      .        . |
     |----------------------------------|
  4. |  2      1     60     76       76 |
  5. |  2      1     76     60       60 |
     |----------------------------------|
  6. |  2      0     32      .        . |
     +----------------------------------+

answered Feb 21, 2021 at 21:49

Nick Cox

37.4k6 gold badges37 silver badges51 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Stata: Reverse Sort

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related