Question 1

Which of the following best describes a census in statistics?

Accepted Answer

A collection of data from every member of a population.

Question 2

A survey asks 1,000 adults if they support a new law, and 600 respond 'yes.' What is the sample in this scenario?

Accepted Answer

The 1,000 adults surveyed.

Question 3

Which of the following is an example of a voluntary response sample?

Accepted Answer

A newspaper asks readers to vote online about a new policy.

Question 4

A statistic is:

Accepted Answer

A numerical measurement describing some characteristic of a sample.

Question 5

Which level of measurement is represented by the following data: 'Freshman, Sophomore, Junior, Senior'?

Accepted Answer

Ordinal

Question 6

A researcher records the years in which a group of athletes won medals: 1998, 2000, 2004. What is the level of measurement?

Accepted Answer

Interval

Question 7

Which sampling method is used when a population is divided into subgroups and a random sample is taken from each subgroup?

Accepted Answer

Stratified sampling

Question 8

A company wants to survey its employees. It randomly selects 5 departments, then surveys every employee in those departments. What sampling method is this?

Accepted Answer

Cluster sampling

Question 9

Which of the following is a quantitative discrete variable?

Accepted Answer

The number of cars sold by a dealership each month.

Question 10

In a survey, every 10th person entering a store is selected for a study. What type of sampling is this?

Accepted Answer

Systematic sampling

Question 11

Which of the following is an example of an observational study?

Accepted Answer

A scientist observes the eating habits of birds without interfering.

Question 12

A parameter is:

Accepted Answer

A numerical measurement describing some characteristic of a population.

Question 13

Which of the following is a ratio level of measurement?

Accepted Answer

Height of students in centimeters.

Question 14

A pollster calls 1,000 randomly selected phone numbers and asks about voting preferences. What type of sampling is this?

Accepted Answer

Simple random sampling

Question 15

Which of the following best describes a categorical (qualitative) variable?

Accepted Answer

The color of a car.

Question 16

A school wants to estimate the average test score of its students. It divides students by grade level and randomly selects students from each grade. What sampling method is this?

Accepted Answer

Stratified sampling

Question 17

Which of the following is NOT a method of probability sampling?

Accepted Answer

Convenience sampling

Question 18

A researcher wants to study the effect of a new fertilizer on plant growth. She applies the fertilizer to half the plants and leaves the other half untreated, then measures growth. What type of study is this?

Accepted Answer

Experiment

Question 19

Which formula would you use to calculate the sample mean $$\bar{x}$$ for a set of $$n$$ observations $$x_1$$, $$x_2$$, ..., x_n$$?

Accepted Answer

$$\bar{x} = \frac{\sum_{i=1}^{n} x_i}{n}$$

Question 20

A survey of 1,200 adults in the United States finds that 44% say they wash their hands after riding public transportation. What is the statistic in this scenario?

Accepted Answer

44%

Fundamental Concepts in Statistics: Data, Sampling, and Measurement

Guida di studio - Domande di pratica

Study guide - Flashcard