Question 1

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

Accepted Answer

A population is the entire group you want to study, while a sample is a subset of that group.

Question 2

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

Accepted Answer

Height in centimeters

Question 3

A researcher wants to study the effect of a new drug on blood pressure. She randomly assigns patients to receive either the drug or a placebo. What type of study is this?

Accepted Answer

Designed experiment

Question 4

Which sampling method involves dividing the population into groups and then randomly selecting all individuals from some of those groups?

Accepted Answer

Cluster sampling

Question 5

If a researcher selects every 5th person from a list of 1,000 employees, which sampling method is being used?

Accepted Answer

Systematic sampling

Question 6

Which of the following statements about bias is TRUE?

Accepted Answer

Sampling bias occurs when the sample is chosen in a way that favors one part of the population.

Question 7

A variable that is not considered in a study but affects the response variable is called:

Accepted Answer

Lurking variable

Question 8

Which of the following best describes a double-blinded experiment?

Accepted Answer

Neither the subjects nor the researchers know who receives which treatment.

Question 9

What is the main purpose of a control group in a designed experiment?

Accepted Answer

To provide a baseline for comparison with the treatment group.

Question 10

Which formula correctly represents the sampling proportion?

Accepted Answer

$$\frac{n}{N}$$

Question 11

A study collects data from a group of people at a single point in time. What type of observational study is this?

Accepted Answer

Cross-sectional study

Question 12

Which of the following is a key difference between correlation and causation?

Accepted Answer

Causation means one variable directly causes changes in another, while correlation only means they are related.

Question 13

A researcher wants to ensure that her sample includes equal numbers of men and women. She divides the population by gender and randomly selects from each group. What sampling method is this?

Accepted Answer

Stratified sampling

Question 14

Which of the following is an example of response bias?

Accepted Answer

A survey question is worded in a way that leads people to answer inaccurately.

Question 15

In a matched-pairs design, what is the main feature?

Accepted Answer

Experimental units are paired, and each pair receives different treatments.

Question 16

Which of the following best describes a convenience sample?

Accepted Answer

A sample composed of individuals who are easy to obtain.

Question 17

A study follows a group of people over 10 years to observe the development of a disease. What type of study is this?

Accepted Answer

Cohort study

Question 18

Which of the following is NOT a feature used to minimize confounding in a designed experiment?

Accepted Answer

Convenience sampling

Question 19

If a variable can only take on specific, separate values (like the number of cars in a parking lot), what type of variable is it?

Accepted Answer

Discrete quantitative variable

Question 20

Which of the following best describes sampling variability?

Accepted Answer

The natural diversity in possible samples that could be selected from a population.

Chapter 1: Data Collection in Introductory Statistics

Guida di studio - Domande di pratica

Study guide - Flashcard