CA Foundation · Quantitative Aptitude · Correlation and Regression
In a linear regression analysis of annual advertising spend (in ₹ lakhs) and sales revenue (in ₹ crores) for 25 retail outlets, the regression equation is estimated as: Sales = 8.5 + 1.2 × Advertising. If an outlet increases advertising spend from ₹15 lakhs to ₹18 lakhs, by how much would sales revenue be predicted to increase?
When advertising increases by ₹3 lakhs (from 15 to 18), the regression slope of 1.2 indicates sales will increase by 1.2 × 3 = ₹3.6 crores. The regression slope represents the marginal impact per unit change in the independent variable.
- A₹3.6 croresCorrect
- B₹2.4 crores
- C₹28.1 crores
- D₹36 lakhs
Explanation
The regression coefficient for Advertising is 1.2, meaning for each additional ₹1 lakh in advertising, sales increase by ₹1.2 crores. The increase in advertising is 18 − 15 = 3 lakhs. Therefore, predicted increase in sales = 1.2 × 3 = 3.6 crores. Option B uses wrong units; option C incorrectly applies the entire equation; option D misinterprets the slope.
Did you get it right without looking?
One question tells you little. A timed set on Correlation and Regression shows your real accuracy, how long you take and where you lose marks.
More Correlation and Regression questions
- The two regression lines of a sample are 3x + 2y = 26 and 6x + y = 31. What are the mean values (x̄, ȳ)?
- For a bivariate data set, the regression coefficient of y on x is 0.9 and that of x on y is 0.4. What is the coefficient of correlation betw…
- For a set of paired observations the coefficient of correlation between advertising spend and sales is r = -0.8. What percentage of the vari…
- Five trainee analysts at a Mumbai brokerage were ranked by two examiners. Examiner A's ranks were 1, 2, 3, 4, 5 and Examiner B's ranks for t…
- In a regression study of household income (X, in ₹ thousands per annum) and household savings (Y, in ₹ thousands per annum) across 50 famili…
- If the correlation coefficient between two variables X and Y is –0.85, which statement best describes their relationship?