When I apply PERWT var, does the online analysis take into consideration of a complex sample design?

1

When I apply PERWT var, does the online analysis take into consideration of a complex sample design?

2

I think you are asking if the online analysis tool uses CLUSTER and STRATA if PERWT is applied, but please let me know if this is not what you are asking. The system does not automatically use the design variables if you select PERWT.

3

Thanks for your reply, Brandon. FYI. after I posted the question, I continued to look into the online analysis tools (i.e., the SDA) and found this statement in http://sda.berkeley.edu/

Complex standard errors : Data collected from stratified and/or cluster samples require special procedures to calculate standard errors and confidence intervals. SDA uses those special procedures for percentages, means, differences between means, and regression coefficients.

Thanks.

4

The information you cited is correct. However, our online tool currently does not utilize the CLUSTER and STRATA variables.

5

Is there a way to get correct standard errors currently when I analyze data using SDA on your website? Please advise.

6

At this time, the only way to generate standard errors that take into account the survey design is to obtain that data through the extract system and calculate the standard errors within a stats package, unfortunately. Note that the CLUSTER and STRATA variables are not perfect, and we recommend using replicate weights to obtain ‘correct’ standard errors. Replicate weights are likewise only available through the extract system.

7

Okay. Thanks. ~Sarah