Question

Use the data set below to answer the question.

x	−2	−1	0	1	2
y	2	2	4	5	5

Find a 90% prediction interval for some value of y to be observed in the future when

x = −1.

(Round your answers to three decimal places.)

Answer 1

predicted val=3.6+-1*0.9=

2.700

SSE =Syy-(Sxy)2/Sxx=

1.100

	s2 =SSE/(n-2)=	0.3667
std error σ              =	=se =√s2=	0.6055

std error prediction interval= s*√(1+1/n+(x0-x̅)2/Sxx)=				0.6904
for 90 % CI value of t=				2.353
margin of error E=t*std error                            =				1.6248
lower prediction bound=sample mean-margin of error =				1.0752
Upper prediction bound=sample mean+margin of error=				4.3248

90% prediction interval =(1.075 , 4.325)