Question 1

Which of the following best defines 'statistics' as used in scientific research?

Accepted Answer

The science of collecting, organizing, analyzing, and interpreting data to make decisions.

Question 2

A university wants to know the average GPA of all its students. They randomly select 200 students and calculate the average GPA to be 3.2. In this scenario, what is the population?

Accepted Answer

All students at the university.

Question 3

Which of the following statements describes a sample statistic?

Accepted Answer

The average height of 100 randomly selected adults in a city.

Question 4

A survey of 1,000 households found that 40% recycle regularly. Is the value 40% a parameter or a statistic?

Accepted Answer

Statistic, because it is based on a subset of the population.

Question 5

Which of the following is an example of a population parameter?

Accepted Answer

The average SAT score of all freshmen at a university.

Question 6

In a study, researchers collect data from 500 patients to estimate the average recovery time from a new surgery. Which branch of statistics is used when they summarize the data using charts and tables?

Accepted Answer

Descriptive statistics

Question 7

A pharmaceutical company uses the results from a sample of 1,000 patients to make conclusions about the effectiveness of a new drug for all patients. Which branch of statistics is being used?

Accepted Answer

Inferential statistics

Question 8

Which of the following best describes the difference between a population and a sample?

Accepted Answer

A population includes all members of a group, while a sample is a subset of that group.

Question 9

A study reports that 32% of 1,000 surveyed 401(k) retirement plan participants do not know how many years their savings will last. What inference might be drawn using inferential statistics?

Accepted Answer

Many 401(k) participants nationwide may have difficulty estimating their retirement needs.

Question 10

Which of the following scenarios illustrates the use of descriptive statistics?

Accepted Answer

Summarizing survey results in a pie chart showing the percentage of people who prefer different ice cream flavors.

Question 11

Suppose a researcher wants to estimate the average number of hours college students sleep per night. She collects data from 300 students at her university. Which term best describes the 300 students?

Accepted Answer

Sample

Question 12

If $$\mu$$ represents the average income of all residents in a city, what is $$\mu$$ called in statistics?

Accepted Answer

Population parameter

Question 13

A researcher calculates the mean test score for a sample of 50 students as $$\bar{x} = 78. $$What does $$\bar{x}$$ represent?

Accepted Answer

Sample statistic

Question 14

Which of the following is NOT a step in the process of statistics?

Accepted Answer

Ignoring outliers in the data without justification.

Question 15

A city council wants to know the proportion of residents who support a new park. They survey 500 residents and find that 60% support the park. Which of the following is true?

Accepted Answer

60% is a sample statistic and may be used to infer the proportion in the entire population.

Question 16

Which formula would you use to calculate the mean of a sample?

Accepted Answer

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

Question 17

A researcher wants to generalize findings from a sample to a population. Which branch of statistics is she using?

Accepted Answer

Inferential statistics

Question 18

Which of the following is an example of data?

Accepted Answer

The number of cars passing through an intersection each hour.

Question 19

A study finds that 21% of 8–11 year-olds have a social media profile. What is the population in this study?

Accepted Answer

All 8–11 year-olds.

Question 20

Which of the following best describes the role of inferential statistics in a medical study?

Accepted Answer

Drawing conclusions about the effectiveness of a treatment for all patients based on results from a sample.

Introduction to Statistics: Key Concepts and Foundations

Guida di studio - Domande di pratica

Study guide - Flashcard