Question 1

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

Accepted Answer

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

Question 2

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

Accepted Answer

Type of smartphone used

Question 3

A researcher records the number of books each student reads in a month. What type of variable is this?

Accepted Answer

Quantitative, discrete variable

Question 4

Which level of measurement allows for meaningful ratios and has a true zero?

Accepted Answer

Ratio

Question 5

A survey asks respondents to rate their agreement with a statement on a scale: strongly agree, agree, disagree, strongly disagree. What is the level of measurement?

Accepted Answer

Ordinal

Question 6

Which sampling method involves dividing the population into homogeneous groups and then randomly sampling from each group?

Accepted Answer

Stratified sampling

Question 7

A quality control engineer selects every 10th item off a production line for inspection. What type of sampling is this?

Accepted Answer

Systematic sampling

Question 8

Which of the following is a potential source of non-sampling error?

Accepted Answer

Response bias due to poorly worded survey questions

Question 9

In an experiment, what is the purpose of a control group?

Accepted Answer

To serve as a baseline for comparison with other treatments

Question 10

A study tracks a group of individuals over 10 years to observe the development of a disease. What type of observational study is this?

Accepted Answer

Cohort study

Question 11

Which of the following best describes the placebo effect?

Accepted Answer

Subjects improve because they believe they are receiving a treatment, even if it is inactive

Question 12

In a double-blind experiment, who is unaware of the treatment assignments?

Accepted Answer

Both the subjects and the researchers in contact with them

Question 13

Which of the following is an example of a matched-pairs design?

Accepted Answer

Pairing twins and giving one twin a treatment and the other a placebo

Question 14

A researcher wants to study the effect of a new teaching method. She randomly assigns students to either the new method or the traditional method. What type of experimental design is this?

Accepted Answer

Completely randomized design

Question 15

Which of the following statements about observational studies is TRUE?

Accepted Answer

They can only establish association, not causation.

Question 16

A researcher divides a population into groups based on income level and then randomly selects some groups to survey all individuals within those groups. What sampling method is this?

Accepted Answer

Cluster sampling

Question 17

Which of the following is an example of response bias?

Accepted Answer

Respondents giving socially desirable answers instead of truthful ones

Question 18

Which of the following best describes a systematic sample?

Accepted Answer

Selecting every kth individual from a population after a random start

Question 19

Which of the following is a key step in the process of statistics?

Accepted Answer

Describing data and performing inference

Question 20

A researcher wants to estimate the average commute time for all workers in a city. She randomly selects 200 workers and calculates the mean commute time. What is the parameter and what is the statistic in this scenario?

Accepted Answer

The mean commute time for all workers is the parameter; the mean for the 200 workers is the statistic.

Chapter 1: Data Collection – Foundations of Statistical Thinking

Guida di studio - Domande di pratica

Study guide - Flashcard