Martina's survey method of selecting every tenth person who enters a neighborhood Mexican restaurant for one week may not produce a representative sample of the people in her neighborhood.
Reasons for the method not to produce a representative sample
Selection bias: Martina's survey may not give a fair result because she only asked people who go to a Mexican restaurant. The people who often go to Mexican restaurants might not be like everyone else in the neighborhood.
People who like Mexican food might go to Mexican restaurants more often. But people who like different kinds of food or come from different cultures may not be included in the survey.
Narrow focus: Asking people who go to a Mexican restaurant only shows what some people who like Mexican food think. It does not consider people who have tried enmoladas con pollo at home, at other restaurants, or in other ways. So, asking people questions may not show the whole picture of who in the neighborhood has tried the dish.
Martina's favorite Mexican dish is enmoladas con pollo, tortillas filled with chicken and cheese and topped with a spicy sauce. She wants to know how many people in her neighborhood have tried this dish. Martina plans to survey every tenth person who enters a neighborhood Mexican restaurant for one week. Will her survey method produce a representative sample of the people in her neighborhood? explain.