Question 1

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

Accepted Answer

A population is the complete collection of all measurements or data being considered, while a sample is a subcollection of members selected from the population.

Question 2

A researcher wants to estimate the average height of all university students. She randomly selects 200 students and measures their heights. In this scenario, what is the population?

Accepted Answer

All university students.

Question 3

Which of the following is an example of a voluntary response sample?

Accepted Answer

A television show asks viewers to call in and express their opinion on a topic.

Question 4

Why are voluntary response samples generally considered to be flawed?

Accepted Answer

They are likely to be biased because respondents decide whether to participate.

Question 5

In a study, 98 girls are born out of 100 random births. The likelihood of this event occurring by chance is less than 5%. What type of significance does this result demonstrate?

Accepted Answer

Statistical significance

Question 6

A new diet program results in an average weight loss of 2.1 kg after one year, which is statistically significant. However, many participants feel this amount is not worth the effort. What does this scenario illustrate?

Accepted Answer

Statistical significance but not practical significance

Question 7

Which of the following is NOT a step in the process of conducting a statistical study?

Accepted Answer

Ignore

Question 8

A survey is conducted by mailing questionnaires to 1,000 randomly selected households, but only 200 respond. What potential pitfall does this scenario illustrate?

Accepted Answer

Nonresponse bias

Question 9

Which of the following best describes statistical thinking?

Accepted Answer

It involves critical thinking and the ability to make sense of results.

Question 10

A study reports that 150% of surveyed employees prefer remote work. What is the most likely issue with this statistic?

Accepted Answer

The percentage exceeds 100%, which is misleading.

Question 11

Which of the following is the correct definition of statistics?

Accepted Answer

The science of collecting, organizing, summarizing, presenting, analyzing, and interpreting data to draw conclusions.

Question 12

A forensic scientist measures shoe print lengths and heights at crime scenes to estimate the height of a criminal. What is the main statistical goal in this scenario?

Accepted Answer

To establish a relationship between shoe print lengths and heights.

Question 13

Which sampling method is most likely to produce unbiased results?

Accepted Answer

Random sampling

Question 14

If a survey question is worded in a way that leads respondents toward a particular answer, what is this called?

Accepted Answer

Loaded question

Question 15

Suppose you want to estimate the proportion of students at your university who own a car. Which of the following would be the best approach?

Accepted Answer

Survey a randomly selected sample of students.

Question 16

Which of the following equations represents the calculation of a sample mean $$\bar{x}$$ from $$n$$ data values $$x_1$$, $$x_2$$, ..., x_n$$?

Accepted Answer

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

Question 17

A survey of 410 human resource professionals found that 14% disqualified job candidates due to social media posts. What is the sample in this study?

Accepted Answer

The 410 human resource professionals surveyed.

Question 18

Which of the following is a potential pitfall when analyzing data?

Accepted Answer

Making conclusions that are unclear to non-statisticians.

Question 19

If a survey has a low response rate, what is the most likely consequence?

Accepted Answer

There is an increased likelihood of bias among respondents.

Question 20

Which of the following best illustrates the concept of practical significance?

Accepted Answer

A new medication reduces blood pressure by 0.5 mmHg, which is statistically significant but too small to affect patient health.

Introduction to Statistics: Concepts, Data, and Sampling

Guida di studio - Domande di pratica

Study guide - Flashcard