A researcher is conducting a survey of political opinions of…
A researcher is conducting a survey of political opinions of people living in Weatherford. The researcher is sampling the population of Weatherford by putting up flyers around town asking people to fill out the survey. The researcher, however, is worried that the characteristics of the people who choose to fill out the survey will be different from the overall population. Which term below best describes the situation in which the people who choose to participate differ significantly from the population?