Same chapter3 marksDifficulty: Medium
When is Spearman's rank correlation used in preference to Karl Pearson's coefficient?
Correlation Analysis
3 marksDifficulty: Medium
Distinguish between positive and negative correlation, giving one example of each.
Original Khojo Papers practice question — not from a past board paper.
Answer
In positive correlation the two variables move in the same direction, as height and weight generally do. In negative correlation they move in opposite directions, as the price of a commodity and the quantity demanded generally do.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
A scatter diagram shows the direction at a glance.
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