Question 1

Which of the following best describes the science of statistics?

Accepted Answer

The science of collecting, organizing, summarizing, and analyzing data to answer questions and/or draw conclusions.

Question 2

Why is context important when interpreting data such as the numbers 90, 95, 80, 75, and 92?

Accepted Answer

Because without context, we cannot determine what the numbers represent.

Question 3

A researcher surveys 200 randomly selected college students about their favorite study spot. What is the population in this scenario?

Accepted Answer

All college students.

Question 4

Which of the following variables is categorical?

Accepted Answer

Type of pet owned

Question 5

What is the main advantage of using a sample instead of a population in a study?

Accepted Answer

A sample is easier and more practical to obtain.

Question 6

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

Accepted Answer

Height of a bridge

Question 7

In the data cycle, which step involves determining which data is available to answer a question?

Accepted Answer

Consider Data

Question 8

Why are percentages or rates often better than raw counts when comparing groups?

Accepted Answer

Because percentages or rates account for differences in group sizes.

Question 9

Given the formula $$	ext{Injury Rate} = \frac{\# 	ext{Injuries}}{\# 	ext{Exposures}}$$, why is this rate more informative than just the number of injuries?

Accepted Answer

It accounts for how many times people were exposed to the risk.

Question 10

A two-way table is most useful for:

Accepted Answer

Organizing two potentially related categorical variables.

Question 11

Which of the following is necessary to establish causality between two variables?

Accepted Answer

Experiment

Question 12

In a medical study, one group receives a new drug and another group receives a harmless pill with no active ingredients. What is the harmless pill called?

Accepted Answer

Placebo

Question 13

What is the main purpose of random assignment in an experiment?

Accepted Answer

To balance out differences in the groups and minimize bias.

Question 14

Which of the following best describes a confounding variable?

Accepted Answer

A variable that has not been accounted for but is causing a change in the response variable.

Question 15

In the example where ice cream sales and drownings both increase during the summer, what is a likely confounding variable?

Accepted Answer

The temperature outside

Question 16

Which of the following is NOT a 'gold standard' for experiments?

Accepted Answer

Using anecdotal evidence

Question 17

A study finds that people who drink more coffee tend to have higher test scores. Which type of study is this most likely to be?

Accepted Answer

Observational study

Question 18

Which of the following best describes the placebo effect?

Accepted Answer

Reacting to a treatment after being told you are receiving the treatment when, in fact, you are not.

Question 19

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

Accepted Answer

The variable that is manipulated to observe its effect

Question 20

A researcher wants to know if a new teaching method improves student performance. She randomly assigns students to either the new method or the traditional method and compares their test scores. What type of study is this?

Accepted Answer

Experiment

Chapter 1: Introduction to Data – Study Notes for Introductory Statistics

Guida di studio - Domande di pratica

Study guide - Flashcard