Design Seed: Why Studies Are Bullshit
IxD is an art, not a science. Trying to make it a science can get you bad data.
Jakob Nielson’s article on Quantitative Analysis explains why sometimes numbers are misleading.
Chris Fahey alerts you to not get caught up in looking for science in the art of user research. He explains how some companies require statistics to prove something works. You can make numbers say anything you want.
I’m not saying statistics are useless and user research doesn’t give data. But user research is about finding patterns in a specific set of users: patterns that should translate into product behavior.