Data Cycle & Questions. Which of these is the LEAST biased statistical question?

1. "Don't you agree that walking to school is best?"
2. "How do you usually travel to school?"
3. "Isn't taking the bus a waste of time?"
4. "Wouldn't you rather cycle to school?"

Answer: "How do you usually travel to school?"

An unbiased question asks for a fact without suggesting what the "correct" answer should be.

The other three options use leading, emotional language that pushes the respondent toward a particular answer.

Population vs Sample. A researcher wants to know the average screen time of all 400 Grade 8 learners at a school, but only interviews 40 of them. What is the SAMPLE?

1. All 400 Grade 8 learners
2. The 40 learners interviewed
3. The school itself
4. The average screen time

Answer: The 40 learners interviewed

The sample is the smaller group actually surveyed, used to estimate results for the whole population.

Population vs Sample. A researcher wants to know the average screen time of all 400 Grade 8 learners at a school. What is the POPULATION?

1. The 40 learners interviewed
2. All 400 Grade 8 learners at the school
3. Only the boys in Grade 8
4. The researcher

Answer: All 400 Grade 8 learners at the school

The population is the entire group being studied — every learner the question is about.

Population vs Sample. A researcher only surveys learners who are already waiting at the school gate before 7am. What type of sample is this?

1. Random sample
2. Representative sample
3. Convenience sample
4. Population

Answer: Convenience sample

Only surveying whoever is easiest to reach (early arrivals) misses latecomers who may use different transport.

This is called a convenience sample, and it introduces bias.

Categorical Data. Five learners name their favourite subject: Maths, Science, Maths, English, Maths. What is the frequency of "Maths"?

1. 2
2. 3
3. 4
4. 5

Answer: 3

Count how many times "Maths" appears in the raw data: Maths, Maths, Maths.