The following MINITAB output presents a 95% confidence interval for the mean ozone level on days when the relative humidity is 40%, and a 95% prediction interval for the ozone level on a Particular day when the relative humidity is 40%. The units of ozone are parts per billion. Predicted Values for New Observations

$\begin{array} { l r c c c } \text { New Obs } & \text { Fit } & \text { SE Fit } & 95.0 \% \text { CI } & 95.0 \% \text { PI } \ 1 & 38.37 & 1.3 & ( 35.82,40.92 ) & ( 21.16,55.58 ) \end{array}$

Values of Predictors for New Observations

Predict the ozone level for a day when the relative humidity is 40%.
A) 35.82
B) 40.0
C) 1.3
D) 38.37

Question

The following MINITAB output presents a 95% confidence interval for the mean ozone level on days when the relative humidity is 40%, and a 95% prediction interval for the ozone level on a Particular day when the relative humidity is 40%. The units of ozone are parts per billion. Predicted Values for New Observations

$\begin{array} { l r c c c } \text { New Obs } & \text { Fit } & \text { SE Fit } & 95.0 \% \text { CI } & 95.0 \% \text { PI } \ 1 & 38.37 & 1.3 & ( 35.82,40.92 ) & ( 21.16,55.58 ) \end{array}$

Values of Predictors for New Observations

Predict the ozone level for a day when the relative humidity is 40%.
A) 35.82 
B) 40.0 
C) 1.3 
D) 38.37

Quizplus · Accepted Answer

The "Fit" column gives the fitted value for ozone level on days with 40% relative humidity, which is 38.37. Therefore, the answer is D.

The Following MINITAB Output Presents a 95% Confidence Interval for the Mean