Question

To find the equation of a regression line, ŷ = ax + b, you need these formulas:Sya=rstb=ỹ alA data set has an r-value of 0.553. If the standard deviation of the x-coordinates is 3.996, and the standard deviation of the y-coordinates is 6.203,what is the slope of the line to three decimal places?A. 0.858B. 1.165C. 2.807D. 0.356

Answer 1

Solution

- The solution steps are given below:

$\begin{gathered} r=0.553 \\ S_x=3.996 \\ S_y=6.203 \\ \\ \text{ We have been given that:} \\ a=r\frac{S_y}{S_x} \\ \\ \text{ Since }a\text{ is the slope, we have that:} \\ a=0.553\times\frac{6.203}{3.996} \\ \\ a=0.8584231...\approx0.858 \end{gathered}$

Final Answer

The slope is 0.858