Question

The average number of people in a family that received welfare for various years is given below.

YEAR	Welfare family size
1969	4.0
1973	3.6
1975	3.2
1979	3.0
1983	3.0
1988	3.0
1991	2.9

y=88.721+ -0.043x

part d.

Find the estimated welfare family size in 1970. (Use your equation from part (b). Round your answer to one decimal place.) _______ people.

Find the estimated welfare family size in 1989. (Use your equation from part (b). Round your answer to one decimal place.)
_______  people.

Use the two points in part (d) to plot the least squares line. (Upload your file below.)

Answer 1

Given that y = 88.721+ -0.043x

x = 1970 then

y = 88.721+ -0.043 ( 1970 ) = 4.0

x = 1989 then

y = 88.721+ -0.043 ( 1989 ) = 3.2

Now the new data is

Year	Welfare family size
1969	4
1973	3.6
1975	3.2
1979	3
1983	3
1988	3
1991	2.9
1970	4
1989	3.2

for above data regression output is

SUMMARY OUTPUT
Regression Statistics
Multiple R	0.834705358
R Square	0.696733035
Adjusted R Square	0.653409183
Standard Error	0.256241497
Observations	9
ANOVA
	df	SS	MS	F	Significance F
Regression	1	1.055937622	1.055938	16.08197	0.005122786
Residual	7	0.459617934	0.06566
Total	8	1.515555556
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%
Intercept	88.52892788	21.24748909	4.16656	0.004207	38.28659991	138.77126
X Variable 1	-0.043040936	0.010732775	-4.01023	0.005123	-0.068419916	-0.017662

from above output now regression equation is

Welfare family size = 88.529 + (- 0.043 year )