Question

The values of y and their corresponding values of y are shown in the table below x 0 1 2 3 4 y 2 3 5 4 6 a) Find the least square regression line y = a x + b. b) Estimate the value of y when x = 10.

Answer 1

Select the data

install analysis tool apk in excel

go tot data>Data analysis >Regression

you will get

SUMMARY OUTPUT
Regression Statistics
Multiple R	0.9
R Square	0.81
Adjusted R Square	0.746667
Standard Error	0.795822
Observations	5
ANOVA
	df	SS	MS	F	Significance F
Regression	1	8.1	8.1	12.78947	0.037386
Residual	3	1.9	0.633333
Total	4	10
	Coefficients	Standard Error	t Stat	P-value	Lower 95%	Upper 95%
Intercept	2.2	0.616441	3.568871	0.037582	0.238208	4.161792
X	0.9	0.251661	3.576237	0.037386	0.099102	1.700898

From output

Regression equation is

y=0.9x+2.2

Solutionb:

For x=10

we have

y=0.9x+2.2

y=0.9*10+2.2

y=11.2

The value of y when x = 10 is 11.2