Q: Which formula would you use to calculate the batting average of a baseball player?

$$\text{Batting Average} = \frac{\text{Number of Hits}}{\text{Number of Times at Bat}}$$

Question 1

A researcher wants to estimate the average number of hours high school students in Kansas City spend on homework each week. She surveys 2500 students from 28 randomly selected schools. What is the population in this study?

Accepted Answer

All high school students in Kansas City

Question 2

Which of the following best describes a parameter?

Accepted Answer

A numerical measurement describing a characteristic of a population

Question 3

A study finds that 1/3 of boys bring protein powder or shakes to gain muscle mass. Is this finding a statistic or a parameter?

Accepted Answer

Statistic, because it is calculated from a sample

Question 4

In a clinical trial, a new drug reduces cholesterol by an average of 10 mg/dL, with a p-value of 0.01. Which statement best describes the result?

Accepted Answer

The result is statistically significant but may not be practically significant

Question 5

A candy bar manufacturer claims that people who have lost a loved one are less likely to eat chocolate. What is the most important consideration when evaluating this claim?

Accepted Answer

Consider the source of the claim

Question 6

A researcher records the number of tests students take in math classes. Is this data discrete or continuous?

Accepted Answer

Discrete, because the number of tests is countable

Question 7

Which of the following is an example of data at the nominal level of measurement?

Accepted Answer

Types of vehicles: sedan, minivan, truck, SUV

Question 8

A college wants to study the effectiveness of a new Statistics course. They randomly select two classes and collect data from all students in those classes. What sampling method is this?

Accepted Answer

Cluster sampling

Question 9

Which of the following best describes a cross-sectional study?

Accepted Answer

Data are measured at one moment in time

Question 10

A sample of 1200 online survey respondents is used to estimate the average time spent on social media. What type of sample is this?

Accepted Answer

Self-selected (voluntary response) sample

Question 11

Which formula would you use to calculate the batting average of a baseball player?

Accepted Answer

$$	ext{Batting Average} = \frac{	ext{Number of Hits}}{	ext{Number of Times at Bat}}$$

Question 12

Which of the following is NOT a reason for gathering data from a sample instead of the entire population?

Accepted Answer

Samples always produce more accurate results than populations

Question 13

A researcher divides college students into groups based on major and then randomly selects students from each group. What sampling method is this?

Accepted Answer

Stratified sampling

Question 14

Which of the following statements is TRUE regarding correlation and causality?

Accepted Answer

Correlation does not imply causality

Question 15

A researcher wants to study the effect of a new teaching method. She randomly assigns students to two groups: one uses the new method, the other uses the traditional method. What type of study is this?

Accepted Answer

Experimental study

Question 16

Which of the following is an example of a convenience sample?

Accepted Answer

Surveying the first 20 people you meet at a shopping mall

Question 17

Which formula represents the proportion of a sample with a certain characteristic?

Accepted Answer

$$\hat{p} = \frac{x}{n}$$

Question 18

A researcher wants to study the effect of exercise on weight loss. She follows a group of people for 6 months and records their weight changes. What type of study is this?

Accepted Answer

Prospective study

Question 19

Which of the following is an example of systematic sampling?

Accepted Answer

Selecting every 5th shopper entering a department store

Question 20

Which of the following is a collection of data from every member of the population?

Accepted Answer

Census

Introduction to Statistics: Populations, Samples, and Data Collection

Guida di studio - Domande di pratica

Study guide - Flashcard