Variables
What is a variable?
A. Something that can be measured and can vary
B. A research conclusion
C. A person conducting research
D. A questionnaire
A. Something that can be measured and can vary
What is your university major?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
A. Nominal
Research question:
Does study time affect exam scores?
What is the independent variable?
A. Exam score
B. Study time
C. Students
D. The exam
B. Study time
Which is a multiple-choice question?
A. How old are you? _____
B. What is your major? Engineering / English / Business / Other
C. Describe your university experience.
D. Why do you study English?
B. What is your major? Engineering / English / Business / Other
A researcher wants to study:
Does sleep affect stress among university students?
What TWO variables must be measured?
Sleep and stress
Which of these is NOT a variable?
A. Age
B. Hours of sleep
C. Stress level
D. The researcher
D. The researcher
How satisfied are you with this class?
Very dissatisfied → Dissatisfied → Neutral → Satisfied → Very satisfied
A. Nominal
B. Ordinal
C. Interval
D. Ratio
B. Ordinal
Does study time affect exam scores?
What is the dependent variable?
Exam score
What type of question is this?
“I feel confident speaking English.”
Strongly disagree → Strongly agree
A. Open-ended
B. Numerical
C. Likert scale
D. Yes/No
C. Likert scale
Which question would better measure sleep?
A. Do you sleep enough?
B. How many hours do you usually sleep each night?
B. How many hours do you usually sleep each night?
Which variable is categorical?
A. Hours of sleep
B. Exam score
C. Major
D. Height
C. Major
Temperature measured in Celsius
A. Nominal
B. Ordinal
C. Interval
D. Ratio
C. Interval
Does exercise affect students' stress levels?
Identify BOTH variables.
IV = Exercise
DV = Stress level
What's wrong with this question?
“Don't you agree that social media is bad for students?”
A. Too short
B. Leading
C. Double-barreled
D. Too many choices
B. Leading
A researcher wants to measure student satisfaction.
Which question is best?
A. Are you happy?
B. University is great, right?
C. How satisfied are you with your university experience?
D. Do you like your university and professors?
C. How satisfied are you with your university experience?
Which variable is continuous?
A. Favorite food
B. Type of transportation
C. University major
D. Hours of sleep
D. Hours of sleep
How many hours did you study yesterday?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
D. Ratio
Does the amount of sleep affect students' academic performance?
Which variable is the outcome being measured?
Academic performance — the dependent variable
What's wrong with this question?
“How satisfied are you with your professors and university facilities?”
A. Leading
B. Too specific
C. Double-barreled
D. Nothing
C. Double-barreled
A researcher asks:
How stressed are you?
Low / Medium / High
What type of variable is stress level as measured here?
A. Nominal
B. Ordinal
C. Interval
D. Ratio
B. Ordinal
Two researchers study exercise.
Researcher A asks:
“What type of exercise do you usually do?”
Researcher B asks:
“How many minutes do you exercise each day?”
Why are these variables measured differently?
A measures exercise using categories; B measures exercise using a numerical/ratio measurement.
Why is temperature in Celsius interval, but hours of sleep ratio?
Both have meaningful/equal numerical differences, but hours of sleep has a true zero. 0 hours means no sleep; 0°C does not mean no temperature.
A researcher asks:
Does the number of hours students spend on social media affect how many hours they study each day?
Identify the IV and DV
IV = Hours spent on social media
DV = Hours spent studying
Improve this questionnaire question:
“Do you exercise regularly?”
“How many days per week do you exercise?”
“How many minutes do you exercise per week?”
“Regularly” is unclear and may mean different things to different participants.
Your research question is:
Does social media use affect university students' sleep?
Your team has 30 seconds to give:
IV = Social media use
DV = Sleep
“On average, how many hours per day do you use social media?”
“On average, how many hours do you sleep each night?”