What is the main purpose of the research? On which day does the couple always go out?

W: Excuse me, could I ask you some questions?
M: Of course.
W: I work for an advertising agency, and I’m doing some research. It’s a new magazine for people like you.
M: People like me? What do you mean?
W: Well, people between 25 and 35 years old.
M: OK.
W: Right. Em, what do you do at the weekend?
M: Well, on Fridays my wife always goes to her exercise class. Then she visits friends.
W: Don’t you go out?
M: Not on Fridays. I never go out on Fridays. I stay at home and watch television.
W: And on Saturdays?
M: On Saturdays, my wife and I always go sailing together.
W: Really?
M: Em, we love it. We never miss it. And then in the evening we go out.
W: Where?
M: Different places. We sometimes go and see friends. We sometimes go to the cinema or a restaurant. But we always go out on Saturday evenings.
W: I see. And now on Sunday, what happens on Sundays?
M: Nothing special. We often go for a walk, and I always cook a big Sunday lunch.
W: Oh! How often do you do the cooking?
M: Em, twice a week, three times a week.
W: Thank you very much. All I need now are your personal details: your name, yours job, and so on. What’s your surname?
M: Robinson.