Same chapter3 marksDifficulty: Medium
State two properties of regression coefficients.
Linear Regression
3 marksDifficulty: Medium
Why are there two lines of regression rather than one?
Original Khojo Papers practice question — not from a past board paper.
Answer
Each line minimises the errors measured in one direction only: the line of y on x minimises the vertical distances and is used to estimate y from x, while the line of x on y minimises the horizontal distances and is used to estimate x from y. The two coincide only when the correlation is perfect.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Using the wrong line for an estimate gives a systematically biased answer.
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