I found a problem with the sampler I was using last week.  It is an uncontrolled random sampler, which presents some problems when doing choice modeling.

To deal with the issue, I created a better one.  This version is a stratified random sampler that samples from each income and auto group (which I need to have samples in all income/auto groups in order to develop and test my auto ownership model).  The sampling process works like this:

1. If there are more than 10 samples for an income/auto group, sample using last week’s random method
2. If there is at least 2 but not more than 10 samples, pick a random sample to be tested, put the rest into the develop group
3. If there is 1 sample, put it in both
4. If there are no samples in the group, print an error to the screen

The code is below:

-A-

Tags: R, sampling, survey data

Posted on Friday, August 1st, 2014 By Andrew Rohne Comments are closed.