Lesson 5.09a-b

5.09a-b Regression lines and least squares Quiz: OCR Further Maths, Unit 2

20 questions

In partnership with Revision Ninja

Lesson 5.09a-b, Regression lines and least squares: 20 multiple choice questions for the OCR Further Maths (H245), Unit 2: Statistics (Y542), written with Revision Ninja.

Host it live on the board and students join with a game code on their own devices, or revise alone with Free Play. The answers are revealed in the game.

Host this setFree Play

The 20 questions

  1. What distance does the least squares regression line of y on x minimise?

    • Absolute vertical distances
    • Perpendicular distances
    • Squared vertical distances
    • Squared horizontal distances
  2. Which point must always lie on the least squares regression line of y on x?

    • Median point
    • Mean point (x̄, ȳ)
    • Modal point
    • Origin (0, 0)
  3. In linear regression analysis, how is a residual value calculated?

    • Predicted minus observed
    • Observed minus mean
    • Observed minus predicted
    • Mean minus predicted
  4. In the regression line equation y = a + bx, what does b represent?

    • Correlation coefficient
    • Gradient
    • Y-intercept
    • Residual sum
  5. What is the primary purpose of calculating the regression line of y on x?

    • Predict x from y
    • Predict y from x
    • Prove causation
    • Calculate correlation coefficient
  6. What is predicting a dependent variable value outside the range of original data called?

    • Extrapolation
    • Interpolation
    • Estimation
    • Integration
  7. What is predicting a dependent variable value inside the range of original data called?

    • Expectation
    • Interpolation
    • Projection
    • Extrapolation
  8. How does the sign of the gradient b relate to the correlation coefficient r?

    • Opposite sign
    • Same sign
    • Always positive
    • No relationship
  9. Given S_xy = 40 and S_xx = 10, what is the gradient b of y on x?

    • 0.25
    • 4
    • 400
    • 30
  10. If mean x is 5, mean y is 12, and b is 2, what is intercept a?

    • 22
    • 10
    • 2
    • 7
  11. For an observed y = 15 and predicted y = 11, what is the residual?

    • 165
    • -4
    • 26
    • 4
  12. Which formula correctly calculates the summary statistic S_xy for n data pairs?

    • (Σxy)^2 / n
    • Σxy - ΣxΣy
    • Σxy - (Σx)(Σy)/n
    • Σx^2 - (Σx)^2/n
  13. Which regression line minimises the sum of squared horizontal distances between points and line?

    • Product moment line
    • Spearman rank line
    • Regression of x on y
    • Regression of y on x
  14. Given S_xx = 25, sum of x is 20, and n = 10, what is sum of x squared?

    • 25
    • 45
    • 65
    • 60
  15. If y = 3x + 4, what is the predicted value of y when x = 5?

    • 12
    • 15
    • 19
    • 23
  16. Which regression line should be used to estimate x when given a value of y?

    • Line of symmetry
    • Regression of x on y
    • Residual line
    • Regression of y on x
  17. What is the formula for the residual sum of squares in regression of y on x?

    • S_yy - S_xy / S_xx
    • S_xy - S_xx S_yy
    • S_xx - (S_xy)^2 / S_yy
    • S_yy - (S_xy)^2 / S_xx
  18. If x is coded as u = x - 10 and y as v = 2y, how relates gradient b to b_uv?

    • b = b_uv - 10
    • b = 2 b_uv
    • b = b_uv / 2
    • b = b_uv + 10
  19. What primary effect does adding an extreme outlier have on a least squares regression line?

    • Large gradient change
    • Zero intercept shift
    • No effect
    • Perfect correlation
  20. If regression gradients of y on x and x on y are 2 and 0.3, what is r^2?

    • 0.6
    • 0.5
    • 0.15
    • 6

All OCR Further Maths quizzes