Question

A sociologist is interested in the relation between x = number of job changes and y = annual salary (in thousands of dollars) for people living in the Nashville area. A random sample of 10 people employed in Nashville provided the following information.

x (number of job changes)	3	5	4	6	1	5	9	10	10	3
y (Salary in $1000)	37	32	34	32	32	38	43	37	40	33

Σx = 56; Σy = 358; Σx² = 402; Σy² = 12,948; Σxy = 2,077

(a) Find x, y, b, and the equation of the least-squares line. (Round your answers for x and y to two decimal places. Round your least-squares estimates to three decimal places.)

x	=
y	=
b	=
ŷ	=	+  x

(b) Draw a scatter diagram for the data. Plot the least-squares line on your scatter diagram.

(c) Find the sample correlation coefficient r and the coefficient of determination. (Round your answers to three decimal places.)

r =
r2 =

What percentage of variation in y is explained by the least-squares model? (Round your answer to one decimal place.)
%

(d) If someone had x = 5 job changes, what does the least-squares line predict for y, the annual salary? (Round your answer to two decimal places.)
thousand dollars

Answer 1