- Mark as New
- Bookmark
- Subscribe
- Mute
- RSS Feed
- Permalink
- Report Inappropriate Content
Hi SAS communities,
I have the following challenge:
I have a logistical regression model including a binary outcome and some categorical and continuous covariates.
The logistical regression model achieved a c-statistic (or area under the ROC curve) of 0.94.
I have then used bootstrapping (unrestricted random sampling) to create 50 data sets (later I will do 1000) put together in one data set, sorted by replicate number (1-50).
Then I run the proc logistic on the large data set, using a 'by replicate' statement.
In the SAS results window I how have 50 separate c-statistics.
Which leads me to the question:
How do I combine the 50 separate c-statistics in the results window, so that I can obtain a single median c-statistics for all the bootstrapped data sets? Preferably also with confidence limits...
I have attached the SAS code in a word file.
Best,
Sebastian Wiberg, MD
Accepted Solutions
- Mark as New
- Bookmark
- Subscribe
- Mute
- RSS Feed
- Permalink
- Report Inappropriate Content
How to store your results into a table:
https://blogs.sas.com/content/iml/2017/01/09/ods-output-any-statistic.html
Look at the PERSIST option on the ODS OUTPUT statement that will allow you to stack them all into one until it's done.
@scwiberg wrote:
Hi SAS communities,
I have the following challenge:
I have a logistical regression model including a binary outcome and some categorical and continuous covariates.
The logistical regression model achieved a c-statistic (or area under the ROC curve) of 0.94.
I have then used bootstrapping (unrestricted random sampling) to create 50 data sets (later I will do 1000) put together in one data set, sorted by replicate number (1-50).
Then I run the proc logistic on the large data set, using a 'by replicate' statement.
In the SAS results window I how have 50 separate c-statistics.
Which leads me to the question:
How do I combine the 50 separate c-statistics in the results window, so that I can obtain a single median c-statistics for all the bootstrapped data sets? Preferably also with confidence limits...
I have attached the SAS code in a word file.
Best,
Sebastian Wiberg, MD
- Mark as New
- Bookmark
- Subscribe
- Mute
- RSS Feed
- Permalink
- Report Inappropriate Content
How to store your results into a table:
https://blogs.sas.com/content/iml/2017/01/09/ods-output-any-statistic.html
Look at the PERSIST option on the ODS OUTPUT statement that will allow you to stack them all into one until it's done.
@scwiberg wrote:
Hi SAS communities,
I have the following challenge:
I have a logistical regression model including a binary outcome and some categorical and continuous covariates.
The logistical regression model achieved a c-statistic (or area under the ROC curve) of 0.94.
I have then used bootstrapping (unrestricted random sampling) to create 50 data sets (later I will do 1000) put together in one data set, sorted by replicate number (1-50).
Then I run the proc logistic on the large data set, using a 'by replicate' statement.
In the SAS results window I how have 50 separate c-statistics.
Which leads me to the question:
How do I combine the 50 separate c-statistics in the results window, so that I can obtain a single median c-statistics for all the bootstrapped data sets? Preferably also with confidence limits...
I have attached the SAS code in a word file.
Best,
Sebastian Wiberg, MD
- Mark as New
- Bookmark
- Subscribe
- Mute
- RSS Feed
- Permalink
- Report Inappropriate Content
Thank you very much! That did the trick...
/Sebastian