We are a senator. We want to sample all of our constituents, but we choose, instead, we sample from the constituents who happen to be listed in the phone book. So these are the people who happen to be, who happen to be listed in the phone book. And so we're not sampling from people who are not in the phone book, who maybe have landlines and they're unlisted, and we're not sampling from people who don't have landlines, who only have mobile phones. And you might say, well, why is that important? Well, think about it. People who decide not to list in the phone book, or people who don't even have a landline, some of those people might be a little bit more concerned about privacy than everyone else.