I got a call from the same number a few minutes ago. The person said he was from "SSRS" and was taking a survey regarding Chicago Jewish households.

I suspect SSRS refers to the company "Social Science Research Solutions."
http://www.ssrs.com/home.php
http://www.ssrs.com/who-we-are.php
http://www.ssrs.com/Cell-Phone-Challenge.php

But I don't know if he was telling the truth about whether he was actually from SSRS.

Anyway, he asked me questions about where I lived, where I grew up, where I planned to live in the next 3-5 years, which branch of Judaism I and my parents identified with, etc.
But also more personal questions like zip code, my age, year of birth, number of household members, their ages, etc.

I doubt whether he was telling the truth when he promised I would stay anonymous.

I hung up before he could get to anything more intrusive.