Suppose a simple linear regression is used to examine the relationship between marathon completion time (minutes) and age (years) for 12 subjects:

DataMean

VarianceAge (X)

20, 24, 32, 33, 36, 42, 48, 50, 55, 61, 62, 71

44.5256.45Completion Time (Y)

195, 184, 202, 200, 223, 243, 219, 230, 270, 230, 255, 260

225.9753.5

That is, the model, timei=

0

0+

1

1agei+

iis estimated where,

0

=160.63

^0=160.63and

1

=1.47

^1=1.47. Further suppose that the estimated residual variance,

2

=221.8

se2=221.8.This question has five parts.(2 marks) A 95 % confidence interval for

1

1is approximately:

a.

(0.845, 2.095)

b.

(-0.845, 2.095)

c.

(0.920, 2.019)

d.

(-0.920, 2.019)

e.

None of the above