This is a small set of data provided to investigate the rela

This is a small set of data provided to investigate the relationship between the age of a lab

computer and the number of service calls on it for the school year. Minitab output for these

data follows. The following data was reported:

X Age of lab computer    1 1 2 2 2 3 3 3 3 4 5 5

Y Number of repair calls 1 0 2 0 3 1 3 2 5 3 5 4

The regression equation is

rep call = - 0.297 + 0.958 age

Predictor      Coef      SE Coef       T            P

Constant    -0.2966    0.8553       -0.35      0.736

age              0.9576    0.2751         3.48     0.006

S = 1.21989     R-Sq = 54.8%     R-Sq(adj) = 50.3%

Analysis of Variance

Source              DF        SS        MS         F          P

Regression          1       18.035   18.035   12.12    0.006

Residual Error    10      14.881    1.488

Total                   11      32.917

Explain what the 95% C.I. (Minitab output below) for x=3 means.

Obs    Fit    SE Fit         95% CI        95% PI

1     2.576    0.355    (1.785, 3.368) (-0.255, 5.407)

95% C.I for the number of service calls for one particular 3 year old computer

95% C.I. for the mean number of service calls for computers that are 3 years old

95% C.I. for the number of service calls for computers that are 3 years old

Solution

ANSWER1:  

95% C.I for the number of service calls for one particular 3 year old computer