Bivariate data, correlation and regression Quiz

1. A regression line is based on data with $x$ from 10 to 20. For which value of $x$ would a prediction be extrapolation?

• A. 12
• B. 15
• C. 18
• D. 25

2. Ice cream sales and drownings are strongly positively correlated. Which statement is most appropriate?

• A. Ice cream sales cause drownings
• B. Drownings cause ice cream sales
• C. A third variable such as hot weather may affect both
• D. The correlation must be a mistake

3. For $y=5x^3$, what is the gradient of the graph of $\log y$ against $\log x$?

• A. 3
• B. 5
• C. $\log5$
• D. $\log3$

4. For $y=5\times100^x$, what is the gradient of the graph of $\log_{10}y$ against $x$?

• A. 100
• B. 2
• C. 5
• D. 0.699

5. A student wants to investigate the effect of revision time on test score. Which is the explanatory variable?

• A. Test score
• B. The student's name
• C. The year group
• D. Revision time