Question 1

Which of the following best describes the main purpose of statistics as defined in the course materials?

Accepted Answer

To collect, organize, analyze, and interpret data in order to make decisions or answer questions.

Question 2

Which of the following is an example of inferential statistics?

Accepted Answer

Using a sample of voters to predict the outcome of a national election.

Question 3

What is the difference between a population and a sample?

Accepted Answer

A population includes all individuals of interest, while a sample is a subset of the population.

Question 4

Which formula would you use to calculate the sample mean $$\bar{x}$$ for a data set with $$n$$ values $$x_1$$, $$x_2$$, ..., x_n$$?

Accepted Answer

$$\bar{x} = \frac{\sum_{i=1}^{n} x_i}{n}$$

Question 5

A researcher wants to estimate the average income of all residents in a city. She randomly selects 200 residents and calculates their average income. In this scenario, what is the population?

Accepted Answer

All residents in the city.

Question 6

Which of the following best describes simple random sampling?

Accepted Answer

Every possible sample of a given size has an equal chance of being selected.

Question 7

Which of the following is NOT a characteristic of descriptive statistics?

Accepted Answer

Making predictions about a population based on a sample.

Question 8

Suppose you want to study the average commute time for employees at a large company. Which method would best ensure a simple random sample?

Accepted Answer

Assign each employee a number and use a random number generator to select participants.

Question 9

Which of the following statements about inferential statistics is true?

Accepted Answer

Inferential statistics involves drawing conclusions about a population based on sample data.

Question 10

A company wants to know if a new training program improves employee productivity. They randomly assign half of their employees to the new program and compare their productivity to the other half. What type of study is this?

Accepted Answer

Designed experiment.

Question 11

Which of the following is an example of an observational study?

Accepted Answer

Recording the heights of students as they enter a classroom without intervening.

Question 12

If a sample is not representative of the population, what is the most likely consequence?

Accepted Answer

The results may not accurately reflect the population.

Question 13

Which of the following best describes the process of statistics?

Accepted Answer

Identify a research objective, collect data, describe data, and make inferences.

Question 14

A census is different from a sample survey because:

Accepted Answer

A census collects data from every individual in the population.

Question 15

Which of the following is a key advantage of using random sampling in a study?

Accepted Answer

It reduces selection bias and increases the likelihood that the sample represents the population.

Question 16

Suppose you want to estimate the average number of hours college students sleep per night. Which of the following would be the best way to obtain a simple random sample?

Accepted Answer

Assign each student a number and use a random number generator to select participants.

Question 17

Which of the following is NOT a step in the process of statistics as outlined in the course materials?

Accepted Answer

Ignoring outliers in the data.

Question 18

If a researcher uses a random number generator to select participants from a list of all students at a university, what type of sampling is being used?

Accepted Answer

Simple random sampling.

Question 19

Which of the following best describes the difference between descriptive and inferential statistics?

Accepted Answer

Descriptive statistics summarizes data; inferential statistics draws conclusions about populations based on samples.

Introduction to Statistics and Collecting Data: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards