Question

A restaurant chain’s owners are trying to decide if they want to open up a franchise in your town. To help them decide, they want to find out how often people in your town go out to eat. A researcher interviews people leaving a local restaurant. Is there a bias in this sampling method? Explain.

Answer 1

There is a bias in this sampling method.
The interviewer only interviews people exiting a local restaurant, which means it's more likely for the people to go out to eat regularly.
If he wanted an interview with no bias, he should go out and interview random people on the street, not in front of any business.

Answer 2

Yes, this is bias. The researcher is most likely asking the people if they liked it, and if there was to be a different type of restaurant would they go to it. What the researcher should do is, send a random amount of anonymous surveys to random homes in the close community, get there ideas and opinions then have them mail it back.