About keeping observation with specified criteria in SAS - sas

Hello and many thanks in advance for your answers and efforts to help newby users in this forum.
i have a sas table with the variables : ID, Year, Month, and Creation date.
What i desire is, per month and year and Creation date to keep only one ID.
My HAVE data is :
ID Year Month Date of creation
1 2019 1 a
1 2019 1 a
1 2019 1 b
1 2019 2 c
1 2019 3 d
1 2020 5 e
2 2019 1 a
2 2019 1 b
2 2019 3 c
3 2021 8 m
3 2021 9 k
My WANT data is
ID Year Month Date of creation
1 2019 1 a
1 2019 1 b
1 2019 2 c
1 2019 3 d
1 2020 5 e
2 2019 1 a
2 2019 1 b
2 2019 3 c
3 2021 8 m
3 2021 9 k
I tried nodup key but it removes ID's.


Your example seems to work fine with NODUPKEY option of PROC SORT. Perhaps you used the wrong BY variables?
data have;
input ID Year Month Creation $ ;
cards;
1 2019 1 a
1 2019 1 a
1 2019 1 b
1 2019 2 c
1 2019 3 d
1 2020 5 e
2 2019 1 a
2 2019 1 b
2 2019 3 c
3 2021 8 m
3 2021 9 k
;
proc sort data=have out=want nodupkey;
by id year month creation ;
run;


You can also use distinct clause from proc sql, it will remove duplicates based on all columns
proc sql;
create table want
as
select distinct * from have;
quit;

Related

Calculate the lag of years by groups of records and between consecutive dates

I would like to ask your help to do the following:
I have a data set that looks like this:
ID Date1 Date2
a 2015 2015
a 2016 2016
a 2017 2018
a 2018 2020
b 2015 2016
b 2018 2019
b 2020 2020
.... ..... .....
Desired output:
ID Lag
a Start
a 1
a 1
a 0
b Start
b 3
b 1
.... ..... .....
I need to count how many years pass from Date2 to Date1 next row for each ID. For example: from Date2 = 2015 (first row) to Date1 2016 (second row) there is 1 year of difference. Can anyone help me please? The first row in the desired output should be set to "Start" to indicate that the lag cannot be calculated because it is the starting point.
Thank you in advance

Simple lag() and a first.
data want ;
set have ;
by ID ;
l = lag(Date2) ;
if not first.ID then diff = sum(Date1,-l) ;
run ;

Replacing variable entries to be the same in each group

I'm working with panel data in Stata, and I have a set up like the following:
ID
year
value
1
2010
1
2011
20
1
2012
20
1
2013
1
2014
2
2010
2
2011
14
2
2012
14
2
2013
14
2
2014
14
and I want to change the blank entries to be the same as the other entries within that ID, for any year. I.e., I want something like the following:
ID
year
value
1
2010
20
1
2011
20
1
2012
20
1
2013
20
1
2014
20
2
2010
14
2
2011
14
2
2012
14
2
2013
14
2
2014
14
What do you recommend?

If the value in variable value are always the same within id you can use this:
* Example generated by -dataex-. For more info, type help dataex
clear
input byte id int year byte value
1 2010 .
1 2011 20
1 2012 20
1 2013 .
1 2014 .
2 2010 .
2 2011 14
2 2012 14
2 2013 14
2 2014 14
end
*Get mean of values within id
bysort id : egen value2 = mean(value)
*Transfer values back to original var to maintain var labels etc. then drop value2
replace value = value2
drop value2

Keep individuals in the same firm by year (Stata)

I have an employer-employee database and need to keep only the individuals that have at least one colleague considering the Firm_id variable, but I don't know how to do this in Stata. My dataset is like this:
Id Firm_id Year
1 50 2010
1 50 2011
2 50 2010
2 50 2011
3 22 2010
3 22 2011
4 22 2010
4 20 2011
In the case above, I would keep only the individuals corresponding to the Id 1 and 2 because they are in the same firm in both of the years in the sample and Id 3 and 4 for 2010.
The output I'm looking for is like:
Id Firm_id Year
1 50 2010
1 50 2011
2 50 2010
2 50 2011
3 22 2010
4 22 2010
Any suggestions on how to perform this in Stata?
Regards,

bysort Id (Firm_id) : keep if Firm_id[1] == Firm_id[_N]
See FAQ here.

Filter specific observations

I have an employer-employee database and need to keep only the individuals that have at least one colleague considering the Firm_id variable, but I don't know how to do this in Stata. My dataset is like:
Id Firm_id Year
1 50 2010
1 50 2011
2 50 2010
2 50 2011
3 22 2010
3 22 2011
4 22 2010
4 20 2011
In case above, I would keep only the individuals corresponding to the Id 1 and 2 because they are in the same firm in both of the years in the sample. Individual number 3 in 2011 and Individual 4 in 2011 would be dropped.
The output I'm looking for is like:
Id Firm_id Year
1 50 2010
1 50 2011
2 50 2010
2 50 2011
3 22 2010
4 22 2010

This works for your data example:
clear
input Id Firm_id Year
1 50 2010
1 50 2011
2 50 2010
2 50 2011
3 22 2010
3 22 2011
4 22 2010
4 20 2011
end
bysort Year Firm_id : keep if Id[1] != Id[_N]
sort Id Year
list

SAS - deleting duplicates on multiple variables

I am trying to delete the observations in my data set that are the same across multiple variables.
For example
RID Admission Date End Date
1 Jan 1 2014 Jan 3 2014>
1 January 1 Jan 3 2014
1 March 2 2014 March 5 2014
2 July 1 2014 July 8 2014
2 July 1 2014 July 8 2014
2 August 9 2014 August 24 2014
I would want to keep all unique admissions for each RID, but delete any observations with the same RID and the same admission/end dates.
Thanks!

PROC SORT DATA=work.yourdatasetin OUT=work.datasetout NODUPLICATES ;
BY rid ;
RUN ;
Something like this might also work.
proc sql;
create table work.yourdatasetout as
select distinct
*
from
work.yourdatasetin;
quit;