What you’ll learn
Compare center and spread.
Key idea
Compute middle-half spread from the two quartiles independently of the median.
Median compares center, quartile difference compares spread; neither determines the other.
Worked example
Classify examples and non-examples for the concept 'Compare center and spread'.
Data A median 5, IQR 2; B median 8, IQR 6. Classify BOTH center and spread comparisons with evidence.
- Compare medians 5 and 8: B median greater.
- IQR is Q3-Q1: A=6-(4)=2, B=11-(5)=6; B IQR greater. These are separate features.
Answer: B median greater; B IQR greater — A median 5, IQR 2; B median 8, IQR 6.
Quick Check
Classify examples and non-examples for the concept 'Compare center and spread'.
Data A median 6, IQR 6; B median 9, IQR 4. Classify BOTH center and spread comparisons with evidence.