For these reasons, telephone random-sample surveys remain the method of choice among American survey researchers.
Timing is everything The most reliable polls are conducted over several days.
This gives interviewers the opportunity to minimize sampling bias by calling back sampled respondents several times, if necessary. Weekday evenings are the best time to poll, since weekdays and weekends find far fewer people home. Those who are at home at these times are differentially older, female and Republican. They may also differ in other ways associated with their spending less time outside the home. Cut-off timing in polls can have a dramatic effect on results.