Statistics Collecting Data

• a

• b

• c

• d

• e

• The graduates who did not respond caused the assumption of independence to be invalid.

• The graduates who did not respond changed the survey from a census to a simple random sample of graduates.

• The graduates who did not respond reduced the sample size and smaller samples are more biased than large samples.

• The graduates who did not respond may represent a group that is homogeneous with respect to income and differs from the graduates who did respond.

• The graduates who did not respond may represent a group that is heterogeneous with respect to income and is similar to the graduates who did respond.

In a certain school, students can choose whether to eat in the school’s cafeteria. A reporter working for the school’s newspaper polled students on their reactions to changes in the menu at the cafeteria. For each student leaving the cafeteria in one 20-minute time period, the reporter used a die to determine whether to stop the student and ask how he or she felt about the new menu. In the reporter’s article it was stated that a random sample of the students showed that 23% of the school’s student population was happy with the new menu. Which of the following statements is true?

• Because each student leaving the cafeteria was randomly selected and could choose to answer or not, this is a random sample of the student population, and the 23% is an accurate measurement of the school population’s view of the new menu.

• Because students self-selected whether to eat in the cafeteria, the sampling method might be biased and the sample might not be representative of all students in the school.

• The survey would have been more effective if the reporter had collected the data in one 10-minute time period rather than in one 20-minute time period.

• The survey would have been more effective if students who cared about the food could have called the reporter to tell how they felt about the new menu, so that only students with opinions on the subject would have been surveyed.

• Because no treatment was imposed on the students eating in the cafeteria, one cannot make any conclusions about the new menu.

• a

• b

• c

• d

• e

What kind of sample is representative of a population? Selected at random and large enough to provide accurate data.

• Unbiased

• Biased

The collection of data such as responses, measurements, or counts, that you want information about

• parameter

• population

• sample

• biased sample

A sample should be

• representative of  only middle school students only

• a very large group

• representative of the population

• representative of people who volunteer

The sample represents the population.

Choose the answer that says "Representative Sample"

• Random Sample

• Biased Sample

• Representative Sample

A sample where characteristics accurately reflect those of the larger population from which the sample is being selected.

• Convenience Sample

• Random Sample

• Representative Sample

• Systematic Sample

_________ is a sample in which each individual or object in the entire population has an equal chance of being selected.

• Sample

• Population

• Random Sample

• Quartile