Question 1

Which of the following best defines statistics as described in the study materials?

Accepted Answer

Statistics is the science of collecting, organizing, summarizing, and analyzing information to draw conclusions or answer questions.

Question 2

A researcher wants to study the average sleep duration of college students. She randomly selects 200 students from her university and records their sleep hours. In this scenario, what is the population?

Accepted Answer

All college students in the world.

Question 3

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

Accepted Answer

Number of vending machines at a school.

Question 4

Suppose a survey asks students to report their grade in Algebra as a percentage. What type of variable is this?

Accepted Answer

Quantitative and continuous.

Question 5

Which of the following variables is measured at the nominal level?

Accepted Answer

Internet provider

Question 6

A researcher divides participants into two groups: one receives a new medication, the other receives a placebo. The researcher then measures blood pressure in both groups. What type of study is this?

Accepted Answer

Designed experiment

Question 7

Which of the following best describes a confounding variable?

Accepted Answer

A variable whose effect cannot be distinguished from another explanatory variable.

Question 8

In a study, researchers found that students who started school at 8:30 am or later had longer sleep duration. What is the response variable in this study?

Accepted Answer

Sleep duration

Question 9

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

Accepted Answer

Number of students in a classroom

Question 10

A survey asks respondents to rate their agreement with the statement 'Working with numbers upsets me' on a scale: strongly agree, agree, disagree, strongly disagree. What is the level of measurement for this variable?

Accepted Answer

Ordinal

Question 11

Which of the following variables is measured at the ratio level?

Accepted Answer

Income (in dollars)

Question 12

A researcher wants to estimate the average number of hours college students exercise per week. She randomly selects 100 students from her university. What is the sample in this scenario?

Accepted Answer

The 100 students selected

Question 13

Which of the following is an example of a continuous variable?

Accepted Answer

Sleep hours

Question 14

Which process step in statistics involves summarizing data through numerical summaries, tables, and graphs?

Accepted Answer

Descriptive statistics

Question 15

Suppose a researcher wants to know if a new teaching method improves test scores. She randomly assigns students to either the new method or the traditional method and compares their scores. What is the explanatory variable?

Accepted Answer

Teaching method

Question 16

Which of the following statements about observational studies is correct?

Accepted Answer

Observational studies only allow researchers to claim association, not causation.

Question 17

A researcher collects data on the type of car owned (Ford, Chevrolet, BMW, etc.). What is the level of measurement for this variable?

Accepted Answer

Nominal

Question 18

Which of the following is an example of a parameter?

Accepted Answer

The mean sleep duration of all high school students in the United States.

Question 19

A researcher wants to study the effect of music on intelligence. She randomly assigns students to different music groups and measures their intelligence after a period of time. What type of study is this?

Accepted Answer

Designed experiment

Question 20

Which of the following best describes a lurking variable?

Accepted Answer

A variable not considered in a study that affects the response variable.

Introduction to the Practice of Statistics: Key Concepts and Applications

Guida di studio - Domande di pratica

Study guide - Flashcard