Question 1

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

Accepted Answer

Statistics is the science of collecting, organizing, summarizing, and analyzing information to draw conclusions or answer questions, providing a measure of confidence in any conclusions.

Question 2

A researcher wants to know the average number of hours college students sleep per night. She surveys 200 students from her university. In this scenario, what is the population?

Accepted Answer

All college students in the world.

Question 3

Which of the following is a parameter?

Accepted Answer

The mean income of all residents in a city.

Question 4

In a study, researchers randomly assign participants to receive either a new medication or a placebo and then measure their blood pressure. What type of study is this?

Accepted Answer

Designed experiment

Question 5

Which of the following variables is qualitative?

Accepted Answer

Education level

Question 6

Which variable below is discrete?

Accepted Answer

Number of students in a classroom

Question 7

A researcher records the brand of smartphone each participant owns. What is the level of measurement for this variable?

Accepted Answer

Nominal

Question 8

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

Accepted Answer

Height of a student (in centimeters)

Question 9

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

Accepted Answer

Ordinal

Question 10

Which of the following best describes a lurking variable?

Accepted Answer

An explanatory variable not considered in a study that affects the value of the response variable.

Question 11

A researcher wants to study the effect of exercise on memory. She randomly assigns participants to exercise or not, then measures their memory scores. What is the explanatory variable?

Accepted Answer

Exercise status (exercise or not)

Question 12

Which of the following is a confounding variable in a study examining the effect of sleep duration on academic performance, if not properly controlled?

Accepted Answer

The number of hours spent studying

Question 13

Which of the following statements about observational studies is correct?

Accepted Answer

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

Question 14

Suppose a variable is measured at the interval level. Which of the following is true?

Accepted Answer

The variable has meaningful differences between values, but no true zero.

Question 15

A researcher collects data on the number of vending machines in different schools. What type of variable is this?

Accepted Answer

Quantitative, discrete

Question 16

Which of the following is an example of a variable measured at the ratio level?

Accepted Answer

Income (in dollars)

Question 17

A researcher wants to estimate the proportion of students who own a car at a university. She surveys a random sample of 500 students. The proportion calculated from this sample is:

Accepted Answer

A statistic

Question 18

Which of the following best describes the process of statistics?

Accepted Answer

Identify the research objective, collect the data, organize and summarize the information, draw conclusions from the data.

Question 19

A researcher records the number of calories consumed by participants each day. What is the level of measurement for this variable?

Accepted Answer

Ratio

Question 20

Which of the following is a real-world example of a continuous variable?

Accepted Answer

Height of trees in a forest

Introduction to the Practice of Statistics: Key Concepts and Foundations

Guida di studio - Domande di pratica

Study guide - Flashcard