i'm trying to create a unique sample dataset with proc surveyselect based on 2 columns.
I have a simple table with person_id and household_id. in this case person_id is my "primary key" which is the main input for creating a sample. BUT i need to make sure that I don't mix household_id between sample and base data.
So if household_id = 123 is the sample, it is not allowed to appear in the base data (even with another person_id) and vice versa.
do you have a handy idea? all my solution pre- or postprocessing will influence the sample sizes.
Thanks!!
E.
As you have found, proc surveyselect does not allow for this sort of constraint. You're going to have to accept a slight distortion in your sampling if you want to accommodate it. My suggestion would be to proceed as follows:
Use proc surveyselect to create a random sample
Identify all household_ids in the sample dataset that are also present in the base dataset. Let's say there are N of these.
Create another sample of size N from the base dataset with all of the household_ids in the original sample excluded.
Put all of the matching household_id rows back in the base dataset, remove them from the original sample, and append the new sample to the original sample.
Related
I have two datasets in SAS. The first looks like this (let's say it is called data 1 (I'm only concerned with two columns of it)
...and the second dataset (let's say it is called data 2) looks like this:
...and I am trying to extract the second column of the first dataset and insert it into the second dataset, to achieve something that looks like this:
Basic Problem Description:
I am trying to extract two columns from a dataset in SAS and add them as rows to a second dataset. The variable names in the first dataset are in a column of their own (entitled 'variable name') and in the second dataset each variable is a column header (a variable in itself) with corresponding data. The images I provided are overly simplistic, as the actual data itself is very long.
Basically, I am trying to find functions in SAS which allow me to do this.
What I have tried
-I have tried to extract the first two columns as a table using proc sql, converted them to a data frame using a data step, sorted them, then used proc transpose to try to convert them from long to wide, then tried to use some sort of append function to tack them on to the second dataset, but append did not work.
-I have tried to merge the two sets, but the merge does not seem to work after using proc transpose.
-I have also tried transposing the second dataset and then merging them, which worked (for some reason) but then I was not able to transpose the data back (so that I can analyze it, which is my purpose in doing all of this).
What functions would I use to go about this process?
Apologies for not providing replicable data, I am more searching for recommendations for functions rather than a detailed hard solution.
To force PROC TRANSPOSE to use a variable as the source for the new variable names use the ID statement. So if you have this first dataset:
data tall;
input fruit $ count ##;
cards;
APPLE 1 PEACH 2 PEAR 2
;
You can use this code to convert it.
proc transpose data=tall out=wide;
id fruit;
var count;
run;
Then if you have another dataset that already has the variables APPLE, PEACH, PEAR etc then just set the two together.
data want;
set wide have ;
run;
I have a table in SAS which contains the format information I want. I want to bin this data into the categories given.
What I don't know how to do is create either an xform or a format file from the data.
An example table looks like this:
TxtLabel Type FmtName label Hlo count
. I FAC1f 0 O 1
1996 I FAC1f 1 2
1997 I FAC1f 2 3
I want to date all years in a different data set as after 1997 OR before 1996.
The problem is that I know how to do this by hard coding it, but these files changes the numbers each time so I'm hoping to use the information in the table to generate the bins rather than hard code them.
How do I go about binning by data using a column from another dataset for my categorization?
Edit
I have two data sets, one which looks like the one I have included and one which has a column titled "YEAR". I want to bin the second data set using the categories from the first. In this case there are two available years in TxtLabel. There are multiple tables like this, I'm looking at how to generate PROC Format code from the table, rather than hard coding the values.
This should run to create the desired format
Proc FORMAT CNTLIN=MyCustomFormatControlData;
run;
You can then use it in a DATA Step, or apply it to a column in a data set.
Binning the data might be construed as 'data set splitting' but your question does not make it clear if that is so. Generic arbitrary splitting is often done with one of these techniques:
wall paper source code resolved from macro variables populated from information garnered in a Proc SQL or Proc FREQ step
dynamic data splitting using hash object for grouping records in memory, and saved to a data set with an .output() call.
Sample code for explicit binning
data want0 want1 want2 want3 want4 want5 wantOther;
set have;
* explicit wall paper;
select (put(year,FAC1f.));
when ('0') output want0;
when ('1') output want1;
when ('2') output want2;
when ('3') output want3;
when ('4') output want4;
when ('5') output want5;
otherwise output wantOther;
run;
This is the construct that source code generated by macro can produce, and requires
one pass to determine the when/output lines that are to be generated
a second pass to apply the lines of code that were generated.
If this is the data processing that you are attempting:
do some research (plenty of info out there)
write some code
make a new question if you get errors you can't resolve
Proc FORMAT
Proc FORMAT has a CNTLIN option for specifying a data set containing the format information. The structure and values expected of the Input Control Data Set (that CNTLIN) is described in the Output Control Data Set documentation. Some of the important control data columns are:
FMTNAME
specifies a character variable whose value is the format or informat name.
LABEL
specifies a character variable whose value is associated with a format or an informat.
START
specifies a character variable that gives the range's starting value.
END
specifies a character variable that gives the range's ending value.
As the requirements of the custom format to be created get more sophisticated you will need to have more information variables in the input control data set.
I am working in SAS Enterprise guide and have a one column SAS table that contains unique identifiers (id_list).
I want to filter another SAS table to contain only observations that can be found in id_list.
My code so far is:
proc sql noprint;
CREATE TABLE test AS
SELECT *
FROM data_sample
WHERE id IN id_list
quit;
This code gives me the following errors:
Error 22-322: Syntax error, expecting on of the following: (, SELECT.
What am I doing wrong?
Thanks up front for the help.
You can't just give it the table name. You need to make a subquery that includes what variable you want it to read from ID_LIST.
CREATE TABLE test AS
SELECT *
FROM data_sample
WHERE id IN (select id from id_list)
;
You could use a join in proc sql but probably simpler to use a merge in a data step with an in= statement.
data want;
merge oneColData(in = A) otherData(in = B);
by id_list;
if A;
run;
You merge the two datasets together, and then using if A you only take the ID's that appear in the single column dataset. For this to work you have to merge on id_list which must be in both datasets, and both datasets must be sorted by id_list.
The problem with using a Data Step instead of a PROC SQL is that for the Data step the Data-set must be sorted on the variable used for the merge. If this is not yet the case, the complete Data-set must be sorted first.
If I have a very large SAS Data-set, which is not sorted on the variable to be merged, I have to sort it first (which can take quite some time). If I use the subquery in PROC SQL, I can read the Data-set selectively, so no sort is needed.
My bet is that PROC SQL is much faster for large Data-sets from which you want only a small subset.
In R I could just write something like model$deviance and model$df.residual, but I can't seem to find any way of doing this in SAS.
Whereas R functions produce an object that has sub-objects that you can extract into a variable, SAS procedures create tables. If you see a statistic in some table that you want to use in another part of your program, you can use the Output Delivery System (ODS) to write that table to a data set, as follows:
1) Use the ODS TRACE ON statement to discover the name of the table (or look it up in the documentation)
2) Use the ODS OUTPUT statement to write the table to a data set.
For example, if you are interested in the many goodness-of-fit diagnostic statistics (including the statistics for deviance and chi-square residuals), you can discover that the "Criteria for Assessing Goodness of Fit" table has the name ModelFit. Therefore, putting
ODS OUTPUT ModelFit=FitStatistics;
inside your PROC GENMOD call will create a data set called "FitStatistics" that contains the statistics you want.
This might be a weird question. I have a data set contains data like agree, neutral, disagree...for many questions. There is not so many observations so for some question, one or more options has frequency of 0, say neutral. When I run proc freq, since neutral shows up in that variable, the table does not contain a row for neutral. I end up with tables with different number of rows. I would like to know if there is a option to show these 0 frequency rows. I will also need to run proc gchart for the same data set, and I will run into the same problem for having different number of bars. Please help me on this. Thank you!
This depends on how exactly you are running your PROC FREQ. It has the sparse option, which tells it to create a value for every logical cell on the table when creating an output dataset; normally, while you would have a cell with a missing value (or zero) in a crosstab, if that is output to a dataset (which is vertical, ie each combination of x and y axis value are placed in one row) those rows are left off. Sparse makes sure that doesn't happen; and in a larger (n-dimensional) crosstab, it creates rows for every possible combination of every variable, even ones that don't occur in the data.
However, if you're just doing
proc freq data=mydata;
tables myvar;
run;
That won't help you, as SAS doesn't really have anything to go on to figure out what should be there.
For that, you have to use a class variable procedure. Proc Tabulate is one of such procedures, and is similar to Proc Freq in its syntax (sort of). You need to either use CLASSDATA on the proc statement, or PRINTMISS on the table statement. In the former case, you do not need to use a format, I don't believe. In the latter case (PRINTMISS), you need to create a format for your variable (if you don't already have one) that contains all levels of the data that you want to display (even if it's just an identity format, e.g. formatting character strings to identical character strings), and specify PRELOADFMT on the proc statement. See this man page for more details.