topic Re: Replacing missing values with mean for each year in SAS Programming

Replacing missing values with mean for each year

farshidowrang — Fri, 24 Apr 2020 14:37:44 GMT

Dear friends,

How can I replace missing values for a specific column for each year? It is very important that two different years do not affect each other. Average should happen within a year.

My dataset is:

year	anomaly
1/1/2014	42
1/2/2014	43
1/3/2014	45
1/4/2014	.
1/5/2014	55
1/6/2014	65
1/7/2014	75
1/8/2014	63
1/9/2014	50
1/10/2014	48
1/11/2014	42
1/12/2014	.
1/1/2015	125
1/2/2015	128
1/3/2015	125
1/4/2015	132
1/5/2015	139
1/6/2015	.
1/7/2015	158
1/8/2015	150
1/9/2015	142
1/10/2015	.
1/11/2015	122
1/12/2015	123
1/1/2016	1135
1/2/2016	1139
1/3/2016	1135
1/4/2016	1144
1/5/2016	.
1/6/2016	1151
1/7/2016	1159
1/8/2016	1144
1/9/2016	1140
1/10/2016	1138
1/11/2016	.
1/12/2016	1129
1/1/2017	5512
1/2/2017	5516
1/3/2017	5514
1/4/2017	5520
1/5/2017	5525
1/6/2017	5529
1/7/2017	5522
1/8/2017	5519
1/9/2017	.
1/10/2017	5518
1/11/2017	5514
1/12/2017	.

Re: Replacing missing values with mean for each year

PaigeMiller — Fri, 24 Apr 2020 14:39:34 GMT

PROC STDIZE will do this, with the METHOD=MEAN and REPONLY options.

Please provide data as a SAS data step. Do not provide data as screen captures.

Re: Replacing missing values with mean for each year

farshidowrang — Fri, 24 Apr 2020 14:43:13 GMT

Thank you
How about for each season?

Re: Replacing missing values with mean for each year

PaigeMiller — Fri, 24 Apr 2020 14:50:36 GMT

@farshidowrang wrote:
Thank you
How about for each season?

Use a BY statement.

Re: Replacing missing values with mean for each year

novinosrin — Fri, 24 Apr 2020 14:54:26 GMT

data have;
input year :mmddyy10. 	anomaly;
format year mmddyy10.;
cards;
1/1/2014	42
1/2/2014	43
1/3/2014	45
1/4/2014	.
1/5/2014	55
1/6/2014	65
1/7/2014	75
1/8/2014	63
1/9/2014	50
1/10/2014	48
1/11/2014	42
1/12/2014	.
1/1/2015	125
1/2/2015	128
1/3/2015	125
1/4/2015	132
1/5/2015	139
1/6/2015	.
1/7/2015	158
1/8/2015	150
1/9/2015	142
1/10/2015	.
1/11/2015	122
1/12/2015	123
1/1/2016	1135
1/2/2016	1139
1/3/2016	1135
1/4/2016	1144
1/5/2016	.
1/6/2016	1151
1/7/2016	1159
1/8/2016	1144
1/9/2016	1140
1/10/2016	1138
1/11/2016	.
1/12/2016	1129
1/1/2017	5512
1/2/2017	5516
1/3/2017	5514
1/4/2017	5520
1/5/2017	5525
1/6/2017	5529
1/7/2017	5522
1/8/2017	5519
1/9/2017	.
1/10/2017	5518
1/11/2017	5514
1/12/2017	.
;


proc sql;
create table want as
select *, ifn(anomaly=.,mean(anomaly),anomaly) as imputed_anomaly
from have
group by year(year) ;
quit;

year	anomaly	imputed_anomaly
01/12/2014	.	52.8
01/05/2014	55	55.0
01/08/2014	63	63.0
01/02/2014	43	43.0
01/04/2014	.	52.8
01/06/2014	65	65.0
01/10/2014	48	48.0
01/07/2014	75	75.0
01/01/2014	42	42.0
01/11/2014	42	42.0
01/09/2014	50	50.0
01/03/2014	45	45.0
01/02/2015	128	128.0
01/01/2015	125	125.0
01/03/2015	125	125.0
01/12/2015	123	123.0
01/11/2015	122	122.0
01/09/2015	142	142.0
01/10/2015	.	134.4
01/08/2015	150	150.0
01/07/2015	158	158.0
01/06/2015	.	134.4
01/05/2015	139	139.0
01/04/2015	132	132.0
01/06/2016	1151	1151.0
01/05/2016	.	1141.4
01/04/2016	1144	1144.0
01/07/2016	1159	1159.0
01/03/2016	1135	1135.0
01/02/2016	1139	1139.0
01/01/2016	1135	1135.0
01/12/2016	1129	1129.0
01/11/2016	.	1141.4
01/10/2016	1138	1138.0
01/09/2016	1140	1140.0
01/08/2016	1144	1144.0
01/12/2017	.	5518.9
01/10/2017	5518	5518.0
01/09/2017	.	5518.9
01/08/2017	5519	5519.0
01/11/2017	5514	5514.0
01/07/2017	5522	5522.0
01/06/2017	5529	5529.0
01/05/2017	5525	5525.0
01/04/2017	5520	5520.0
01/03/2017	5514	5514.0
01/02/2017	5516	5516.0
01/01/2017	5512	5512.0

Re: Replacing missing values with mean for each year

novinosrin — Fri, 24 Apr 2020 15:11:16 GMT

data have;
input year :mmddyy10. 	anomaly;
format year mmddyy10.;
cards;
1/1/2014	42
1/2/2014	43
1/3/2014	45
1/4/2014	.
1/5/2014	55
1/6/2014	65
1/7/2014	75
1/8/2014	63
1/9/2014	50
1/10/2014	48
1/11/2014	42
1/12/2014	.
1/1/2015	125
1/2/2015	128
1/3/2015	125
1/4/2015	132
1/5/2015	139
1/6/2015	.
1/7/2015	158
1/8/2015	150
1/9/2015	142
1/10/2015	.
1/11/2015	122
1/12/2015	123
1/1/2016	1135
1/2/2016	1139
1/3/2016	1135
1/4/2016	1144
1/5/2016	.
1/6/2016	1151
1/7/2016	1159
1/8/2016	1144
1/9/2016	1140
1/10/2016	1138
1/11/2016	.
1/12/2016	1129
1/1/2017	5512
1/2/2017	5516
1/3/2017	5514
1/4/2017	5520
1/5/2017	5525
1/6/2017	5529
1/7/2017	5522
1/8/2017	5519
1/9/2017	.
1/10/2017	5518
1/11/2017	5514
1/12/2017	.
;

data want;
 do _n_=1 by 1 until(last.year);
  set have;
  by year groupformat;
  format year year.;
  _n=sum(n(anomaly),_n);
  _sum=sum(anomaly,_sum);
 end;
 _mean=_sum/_n;
 do _n_=1 to _n_;
  set have;
  if nmiss(anomaly) then anomaly=_mean;
  output;
 end;
 drop _:;
run;

year	anomaly
2014	42.0
2014	43.0
2014	45.0
2014	52.8
2014	55.0
2014	65.0
2014	75.0
2014	63.0
2014	50.0
2014	48.0
2014	42.0
2014	52.8
2015	125.0
2015	128.0
2015	125.0
2015	132.0
2015	139.0
2015	134.4
2015	158.0
2015	150.0
2015	142.0
2015	134.4
2015	122.0
2015	123.0
2016	1135.0
2016	1139.0
2016	1135.0
2016	1144.0
2016	1141.4
2016	1151.0
2016	1159.0
2016	1144.0
2016	1140.0
2016	1138.0
2016	1141.4
2016	1129.0
2017	5512.0
2017	5516.0
2017	5514.0
2017	5520.0
2017	5525.0
2017	5529.0
2017	5522.0
2017	5519.0
2017	5518.9
2017	5518.0
2017	5514.0
2017	5518.9

Re: Replacing missing values with mean for each year

farshidowrang — Fri, 24 Apr 2020 16:18:06 GMT

Dear sir,

I have tested

It's not working for each year

Re: Replacing missing values with mean for each year

PaigeMiller — Fri, 24 Apr 2020 16:32:02 GMT

You can't just say "it's not working". We don't how to help if that's all the information you give us.

Show us the LOG from the code. Show us the output if it doesn't have the right answer.

Re: Replacing missing values with mean for each year

farshidowrang — Fri, 24 Apr 2020 16:38:38 GMT

Dear sir,

It did not replace it with the mean of each year.

proc stdize data=have out=imputed_have
method=mean reponly;
var anomaly;
run;

Re: Replacing missing values with mean for each year

PaigeMiller — Fri, 24 Apr 2020 16:56:01 GMT

You did not use a BY statement.

Also, sometimes we confused ourselves by calling a variable YEAR when it does not contain YEAR, it contains month/day/year. So you need to create a new variable in your data set that contains only the YEAR value, not the month/day/year. Let's call this new column YEAR2.

Then, adding

BY YEAR2;

into PROC STDIZE will work.