Question 1

Which of the following best describes the difference between a parameter and a statistic?

Accepted Answer

A parameter is a numerical summary based on the population, while a statistic is a numerical summary based on a sample.

Question 2

A researcher wants to estimate the average number of hours college students sleep per night. She surveys 200 students from her university. What is the population in this study?

Accepted Answer

All college students.

Question 3

Which of the following is an example of a discrete quantitative variable?

Accepted Answer

The number of vending machines at a school.

Question 4

A study collects the number of days per week a student eats lunch at school. What is the level of measurement for this variable?

Accepted Answer

$$	ext{Ratio}$$

Question 5

Which of the following best describes an observational study?

Accepted Answer

A study in which the researcher observes individuals and measures variables of interest but does not attempt to influence the responses.

Question 6

In a case-control study, which of the following is true?

Accepted Answer

Individuals with certain characteristics are matched with those who do not have those characteristics, and the researcher looks back in time to examine exposure.

Question 7

Which of the following is an example of a nominal level of measurement?

Accepted Answer

Type of pet owned (dog, cat, bird, etc.).

Question 8

A study finds that 32% of high school students reported being bullied in the past month. Is this value a parameter or a statistic?

Accepted Answer

Statistic, because it is based on a sample of students.

Question 9

Which of the following best describes a lurking variable?

Accepted Answer

A variable that was not considered in a study but affects the value of the response variable.

Question 10

A researcher wants to know if a new medication reduces blood pressure. She randomly assigns 100 patients to receive the medication and 100 to receive a placebo, then compares their blood pressure after 6 months. What type of study is this?

Accepted Answer

Experiment

Question 11

Which of the following variables is both quantitative and continuous?

Accepted Answer

Height of a person

Question 12

Which of the following statements about confounding variables is correct?

Accepted Answer

Confounding occurs when the effects of two or more explanatory variables are not separated.

Question 13

A survey asks respondents to rate their happiness on a scale from 1 to 10. What is the level of measurement for this variable?

Accepted Answer

$$	ext{Ordinal}$$

Question 14

Which of the following is an example of a cross-sectional study?

Accepted Answer

A study that collects information about individuals at a specific point in time.

Question 15

Which of the following best describes a continuous variable?

Accepted Answer

A variable that can take on any value within a given range.

Question 16

A researcher collects data on the number of vending machines in each school in a district. What type of variable is this?

Accepted Answer

Quantitative, discrete

Question 17

Which of the following is an example of a ratio level of measurement?

Accepted Answer

Number of days per week a student eats lunch

Question 18

In a cohort study, which of the following is true?

Accepted Answer

Individuals are followed over a long period of time to observe outcomes.

Question 19

Which of the following best describes the explanatory variable in a study?

Accepted Answer

The variable that is manipulated or categorized to explain changes in the response variable.

Question 20

A study finds that 18% of the population voted in the 2018 national midterm election. Is this value a parameter or a statistic?

Accepted Answer

Parameter, because it describes the entire population.

Introduction to Statistics: Concepts, Variables, and Study Design

Guida di studio - Domande di pratica

Study guide - Flashcard