Question 1

Which of the following best defines a statistic in the context of data analysis?

Accepted Answer

A numerical summary based on a sample.

Question 2

A researcher wants to study the effect of a new medication on blood pressure. She randomly assigns 100 patients to receive either the medication or a placebo and measures their blood pressure after 6 weeks. What type of study is this?

Accepted Answer

Designed experiment

Question 3

Which of the following variables is best classified as continuous?

Accepted Answer

The amount of rainfall in millimeters during a storm

Question 4

A survey asks respondents to indicate their level of agreement with a statement on a scale from 1 (strongly disagree) to 5 (strongly agree). What is the level of measurement for this variable?

Accepted Answer

Ordinal

Question 5

Which of the following is an example of a stratified sample?

Accepted Answer

Dividing a population of students by major and randomly selecting an equal number from each major

Question 6

A researcher collects data on the number of hours students study per week and their final exam scores. Which variable is the response variable?

Accepted Answer

Final exam score

Question 7

Which of the following best describes sampling bias?

Accepted Answer

The technique used to obtain the sample favors one part of the population over another.

Question 8

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

Accepted Answer

$$k = 20$$

Question 9

Which of the following is a key difference between a cluster sample and a stratified sample?

Accepted Answer

In a cluster sample, all individuals in selected groups are surveyed; in a stratified sample, a random sample is taken from each group.

Question 10

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

Accepted Answer

Cohort study

Question 11

Which of the following is an example of response bias?

Accepted Answer

Survey respondents give answers they think are socially acceptable rather than their true opinions.

Question 12

In a matched-pairs design, which of the following is true?

Accepted Answer

Each experimental unit is paired with another that is similar in some way, and each receives a different treatment.

Question 13

Which of the following best describes a parameter?

Accepted Answer

A numerical summary of a population.

Question 14

A researcher wants to estimate the average income of all households in a city. She randomly selects 100 households and calculates the average income for these households. What type of error is present because she used a sample instead of the entire population?

Accepted Answer

Sampling error

Question 15

Which of the following variables is measured at the ratio level?

Accepted Answer

Number of days per week a student eats school lunch

Question 16

A quality control engineer wants to obtain a systematic sample of 25 bottles from a production line of 500 bottles. What is the correct procedure?

Accepted Answer

Select every 20th bottle after randomly choosing a starting point between 1 and 20.

Question 17

Which of the following is NOT a source of nonsampling error?

Accepted Answer

Sampling error

Question 18

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

Accepted Answer

Both the experimental units and the researchers in contact with them

Question 19

Which of the following best describes a convenience sample?

Accepted Answer

A sample in which the individuals are easily obtained and not based on randomness.

Question 20

A researcher is interested in the effect of temperature and humidity on plant growth. She sets up an experiment with three temperature levels and two humidity levels, randomly assigning plants to each combination. What is the total number of treatments in this experiment?

Accepted Answer

$$3 	imes 2 = 6$$

Chapter 1: Data Collection – Structured Study Notes for Statistics Students

스터디 가이드 - 연습 문제

학습 가이드 - 플래시카드