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 to be studied, while a sample is a subset of that group.

Question 2

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

Accepted Answer

Nationality

Question 3

A researcher collects the heights of all students in a class. What type of variable is height?

Accepted Answer

Continuous quantitative

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 satisfaction as 'Very Satisfied', 'Satisfied', 'Neutral', or 'Dissatisfied'. What is the level of measurement for this variable?

Accepted Answer

Ordinal

Question 6

Which of the following best describes a simple random sample?

Accepted Answer

Every possible sample of the desired size has an equally likely chance of being chosen.

Question 7

A researcher divides a population into non-overlapping groups based on age and then randomly selects individuals from each group. What sampling method is this?

Accepted Answer

Stratified sampling

Question 8

In a systematic sample, if the population size is $$N = 1000$$ and the sample size is $$n = 50$$, what is the value of $$k$$?

Accepted Answer

$$k = 20$$

Question 9

Which of the following is a source of nonresponse bias?

Accepted Answer

Some individuals selected for the sample do not respond and their opinions differ from those who do respond.

Question 10

A study tracks a group of individuals over 20 years to observe the development of a disease. What type of observational study is this?

Accepted Answer

Cohort

Question 11

Which of the following statements about observational studies is correct?

Accepted Answer

They can only establish association, not causation.

Question 12

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

Accepted Answer

To serve as a baseline for comparison with other treatments.

Question 13

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

Accepted Answer

Neither the subject nor the researcher knows which treatment the subject receives.

Question 14

A researcher wants to test the effect of three different fertilizers on plant growth. She randomly assigns 10 plants to each fertilizer group and measures the growth after 8 weeks. What type of experimental design is this?

Accepted Answer

Completely randomized design

Question 15

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

Accepted Answer

Measuring blood pressure of patients before and after taking a medication.

Question 16

A researcher uses a table of random numbers to select a sample from a population. What type of sampling is this?

Accepted Answer

Simple random sampling

Question 17

Which of the following is a potential source of response bias in a survey?

Accepted Answer

The wording of the questions influences the answers

Question 18

If a researcher selects 5 classes at random from a school and surveys all students in those classes, what sampling method is being used?

Accepted Answer

Cluster sampling

Question 19

Which of the following best describes the difference between stratified and cluster sampling?

Accepted Answer

Stratified sampling divides the population into homogeneous groups and samples from each; cluster sampling samples all individuals from randomly selected groups.

Question 20

A researcher wants to estimate the average commute time for all employees at a large company. She selects every 10th employee from an alphabetical list. What type of sampling is this?

Accepted Answer

Systematic sampling

Chapter 1: Data Collection – Introductory Statistics Study Guide

Guida di studio - Domande di pratica

Study guide - Flashcard