I am looking to build a regression model to understand the impact of signing up on a website with sales. I took a random 200k sample of active customers (out of the 30 million or so).. it turns out none of them signed up on the website. So then, I took the population of people who signed up on the website in a given month (~30k).
So I have a dataset that consists of a random sample of 200k customers who did not sign up and 30k customers who did sign up.... I want to build my regression off of this.
Is there anything I need to take into consideration here? Do I need to apply sample weights or something like that, or is my test design ok?
Thank you for the help.