Suppose you are conducting a survey to determine what portion of voters in your town supports a particular candidate for mayor. Consider each of the following methods for sampling the voting population of your town. State whether each method is likely to produce a representative sample and explain your reasoning.
Samples from specific situations are not likely to create representative random samples.
Call one number from each page of an online phone listing for your town between noon and 2 p.m.
Not likely; this samples the population of people with phone numbers listed online that are home midday.
Also, we only get responses from those who agree to participate.
Survey each person leaving a local grocery store.
Survey each person leaving a local movie theater.
Walk around downtown and survey every fourth person you see.
Could you make a representative sample by surveying a few people from each of the situations described in parts (a) through (d)? Explain, and consider what problems might still remain.