In a survey taken in 1985, of the 21 households surveyed in Middletown, Ohio, the proportion of households having a personal computer was 11%. The U.S. government census data for 2005 suggested that 38% of households in the United States had a personal computer.

Which statement(s) below support the large discrepancy between the sample proportion of households having a personal computer in 1985 and the population proportion of households having a personal computer in 2005?

1. The sample size was too small.
2. The sample was not truly random.
3. The data from 1985 to 2005 have changed.
4. The sample statistic is equal to the population parameter.

Only statements I, II, and III support the discrepancy.

Only statements I, III, and IV support the discrepancy.

Only statements II and III support the discrepancy.

Only statement IV supports the discrepancy.

Which of the following sampling techniques could result easily in biased statistics?

1. A government employee decides to wait at a bus stop to survey people about whether they support a certain candidate in an upcoming federal election.
2. A student council representative puts up a poster in the school that asks students whether they favor longer class periods. The students interested in answering the survey would then e-mail their answer to the student council for the data to be analyzed.
3. The principal of a large school assigns a number to each student in the school, places the numbers in a drum, and selects 75 numbers without replacement. He then compares these numbers with the numbered list of students and surveys these students about whether they favor a proposed new policy that requires students to wear indoor shoes only when in the school.
4. The owner of a small business of 300 employees draws 35 employee names out of the 300 names in a hat to survey them to determine the satisfaction level of employees with respect to healthcare benefits offered to all employees.

Statements I and II

Statements II and III

Statements I and IV

Statements II and IV

The dean at a large college wants to determine the average SAT scores for students who apply from New York. She surveyed 95 students from New York and discovered a mean SAT score of 1,509.

Which of the statements below represent the statistic and the population, respectively, of the survey?

1. The mean SAT score of all students from New York
2. The mean SAT score of 95 students from New York
3. The 95 students who apply to the college from New York
4. All students who apply to the college from New York

Statements I and II

Statements II and III

Statements I and IV

Statements II and IV

In an attempt to document the percentage of teenagers in the United States who play video games for more than 4 hours per day, the group Concerned Citizens for Teenage Welfare surveyed 2,000 teenagers randomly selected from across the United States. It was discovered that 33% of teenagers surveyed play video games for more than 4 hours per day. Concerned Citizens for Teenage Welfare released a statement saying: "If you are the parent of the 33% of teenagers in America who play video games for more than 4 hours per day, you should consider engaging your teen in at least one other activity per day."

What does the Concerned Citizens for Teenage Welfare statement represent?

It represents the random sample.

It represents the population parameter.

It represents the sample statistic.

It represents an inference about teenagers in the United States.

A student, following an upcoming federal election, recalls hearing the incumbent president state that "the national unemployment rate for the United States of America is 4.5%." The 4.5% represents _______.

a parameter only

a statistic only

a parameter or a statistic

neither a parameter nor a statistic