Section 1.4 Statistics

Large samples usually give reasonably accurate results, no matter how they are drawn.

false

The way that a question in a survey is worded rarely has an effect on the responses.

false

Who's calling, please? Random-digit dialing is a sampling method in which a computer generates phone numbers at random to call. In recent years, caller ID has become popular. Do you think that caller ID increases the bias in random digit dialing? Explain

non response bias

A bank sent out questionnaires to a simple random sample of 500 customers asking whether they would like the bank to extend its hours. Eighty percent of those returning the questionnaire said they would like the bank to extend its hours. Of the 500 questionnaires, 20 were returned.- what bias?

non-response bias

People who are asked to participate in a study but refuse to do so are called __________

non-response bias

A large sample is useful only if it is drawn by a method that is likely to represent the ____________ well.

population

In a study of the effectiveness of wearing seat belts, a group of people who had survived car accidents in which they had not worn seat belts reported that seat belts would not have helped them.- what bias?

sampling bias

Who's calling, please? Many polls are conducted over the telephone. Some polling organizations choose a sample of phone numbers to call from lists that include landline phone numbers only, and do not include cell phones. Do you think this increases the bias in phone polls? Explain.

sampling bias

A police department conducted a survey in which police officers interviewed members of their community to ask their opinions on the effectiveness of the police department. The police chief reported that 90% of the people interviewed said that they were satisfied with the performance of the police department.- what bias?

self-interest bias

A sign in a restaurant claims that 95% of their customers believe them to have the best food in the world.- what bias?

self-interest bias

An e-store that sells cell phone accessories reports that 98% of its customers are satisfied with the speed of delivery.- what bias?

self-interest bias

To estimate the prevalence of illegal drug use in a certain high school, the principal interviewed a simple random sample of 100 students and asked them about their drug use. Five percent of the students acknowledged using illegal drugs.- what bias?

social acceptability bias

Surveys with many nonresponders often provide misleading results.

true

A television newscaster invites viewers to tweet their opinions about whether the U.S. Congress is doing a good job in handling the economy. More than 100,000 people send in an opinion.- what bias?

voluntary response bias

To determine his constituents' feelings about election reform, a politician sends a survey to people who have subscribed to his newsletter. More than 1000 responses are received.-what bias?

voluntary response bias

_______________are highly unreliable in part because people who have strong opinions are more likely to participate

voluntary response survey