What's best for your project is difficult to say without context.
I'd just draw your attention to -min()- and -max()-. You might want to
work with -min(date1, date2)- or -max(date1, date2)- bearing in mind
that -min()- and -max()- ignore missings to the extent possible.
Your final line is legal for numeric variables.
Nick
[email protected]
Tomas M
Suppose I have a several date variables, each constructing a timeline of
events.
Say, Date 1 < date 2 < date 3 < date 4.
They are supposed to follow in chronological order.
For a few cases, suppose date 3 occurs before date 2 (i.e. the values in
Date 3 are in error).
My question is, if I wanted to calculate the window from (Date 1 to Date
2), or (Date 1 to Date 3), would it be better to fill in the data with
the most conservative estimate possible?
For example, if the values for Date 3 are in error, then the LEAST
conservative estimate for (Date 1 to Date 3) is equal to (Date 1 to Date
2). And by saying (Date 1 to Date 2), etc., I mean calculating the
difference between the dates.
Conversely, the MOST conservative estimate for (Date 1 to Date 3) is
equal to (Date 1 to Date 4), since Date 3 is supposed to occur between
Date 2 and 4.
What should I do with these missing values then?
Should I just exclude from analyses?
Would this coding work?
replace Date_3 = Date_2 if Date_3==.
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