Statistics and Bias

A poll about favorite sports is taken from 100 seniors in a high school where the senior class has 575 students. 23% of respondents said that baseball was their favorite sport.
The "100" is the ______

• Sample Size

• Population Size

• Statistic

• Parameter

A teacher puts all her students' names in hat, then selects 3 names from the hat. These students will take a standardized test.

• Convenience

• Systematic

• Stratified

• Simple Random

Which of the following doesn’t result in some form of bias?

• Choosing AP students to survey regarding their GPA in order to estimate the average GPA in a school.

• Polling a group of potential voters outside a Republican campaign office in order to estimate the proportion of city residents who favor a particular candidate.

• Surveying people who work in the marketing department of a large corporation in order to assess employee satisfaction with management policies.

• Choosing a stratified random sample of juniors and seniors at a high school in order to estimate the proportion of juniors and seniors who plan to go on to college.

• Asking shoppers leaving a grocery store if they think groceries should cost less in order to estimate the proportion of city residents who think groceries cost too much.

A department store mails a customer satisfaction survey to people who make credit card purchases at the store. This month, 45,000 people made credit card purchases. Surveys are mailed to 1000 of these people, chosen at random, and 137 people return the survey form. Identify the population and the sample.

• P: 45,000 people who made credit card purchases.

  S: 137 returned surveys.

• P: 1,000 people that made credit card purchases who received a survey

  S: 137 returned surveys.

• P: 45,000 people who made credit card purchases.

  S: 1,000 people that made credit card purchases who received a survey

• P: All people who that have made credit card purchases.

  S: 1,000 people that made credit card purchases who received a survey

A teacher wants to know the average time spent doing homework by the students in her class of 20 girls and 5 boys.

She selects the five closest to her desk.

• simple random

• Self Selected.

• Convenience

• Systematic Random

A teacher wants to know the average time spent doing homework by the students in her class of 20 girls and 5 boys.

She picks the student in every 5th seat.

• Simple Random

• Systematic

• voluntary response

• convenience

16 out of the 20 people who called into a radio station said that they enjoy the station's morning programming. What type of bias is demonstrated here?

• Voluntary Response Bias

• Nonresponse Bias

• Undercoverage Bias

Why should samples be randomly selected?

• for control

• to reduce bias

• so we don't get the same answers from everyone

A school surveys all 7th grade boys to determine what to sell in the school store.  This sample is _________.

• Biased

• Unbiased

• Representative

• Peanut butter cups

A toy store owner tracking how much kids spend each month on toys. Which choice best represents a population?

• All of the kids who buy toys.

• 227 wealthy kids.

• 228 boys age 7 - 15

• 235 kids from age 10 to 15.