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

A researcher wants to know the average height of all university students. She measures the height of 200 randomly selected students. In this context, what is the population?

Accepted Answer

All university students.

Question 3

Which of the following is a numerical variable?

Accepted Answer

The number of hours worked each week.

Question 4

Suppose you want to know the most common eye color among students at a college. You survey 150 students about their eye color. What is the variable in this study, and what type is it?

Accepted Answer

Eye color; categorical variable.

Question 5

Which of the following best explains why organizing data is important in statistics?

Accepted Answer

Organizing data helps us see patterns that may not be obvious in raw data.

Question 6

A two-way table is most useful for which of the following purposes?

Accepted Answer

Displaying the relationship between two categorical variables.

Question 7

In a study, researchers want to know if a new medication lowers blood pressure. The group that receives the medication is called the:

Accepted Answer

Treatment group.

Question 8

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

Accepted Answer

Conducting an experiment with random assignment.

Question 9

A confounding variable is best described as:

Accepted Answer

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

Question 10

A study finds that as ice cream sales increase, the number of drownings also increases. Which of the following is the most likely explanation?

Accepted Answer

There is a confounding variable, such as temperature, affecting both ice cream sales and drownings.

Question 11

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

Accepted Answer

Type of flower planted in a garden.

Question 12

In a medical experiment, what is the purpose of a placebo?

Accepted Answer

To serve as a harmless treatment given in place of the actual treatment, helping to measure the placebo effect.

Question 13

Which of the following best describes a double-blind experiment?

Accepted Answer

Neither the participants nor the researchers know who is in the treatment or control group.

Question 14

A researcher wants to compare the injury rates of different sports. Why is it important to know the total number of players in each sport?

Accepted Answer

Because comparing rates (such as injuries per 1,000 participants) allows for fair comparison between sports of different sizes.

Question 15

Which of the following is NOT a standard for a good experiment?

Accepted Answer

Assigning subjects to groups based on their preferences.

Question 16

Suppose a study finds that people who exercise regularly have lower blood pressure. The study did not assign people to exercise or not. What type of study is this?

Accepted Answer

Observational study.

Question 17

Which of the following best describes the data cycle in statistics?

Accepted Answer

Ask questions, consider data, analyze data, interpret data.

Question 18

A researcher randomly assigns one group of children to eat ice cream and another group to eat pretzels, then measures how much fun they had. What type of study is this?

Accepted Answer

Experiment.

Question 19

Which of the following is a correct formula for calculating a percentage from a two-way table?

Accepted Answer

$$ 	ext{Percentage} = \frac{	ext{Number in category}}{	ext{Total number}} 	imes 100 $$

Question 20

Which of the following statements about statistics is TRUE?

Accepted Answer

Results in statistics are always uncertain and must be interpreted carefully.

Introduction to Statistics: Understanding Data, Classification, and Study Design

Guida di studio - Domande di pratica

Study guide - Flashcard