# Inference for Simple Linear Regression in MINITABTM

## Chapter 9, Printout 1

Note: The data set for this example is identical to that for Printout 1 of Chapter 4. The procedures are similar to those in Sections 1 and 2 of the "Fitting a Line by Least Squares" example, but additional steps are shown for inferences in simple linear regression.

### Section 1: Making a Fitted Line Plot

1. Launch MINITAB.

2. Enter the data.

• Name Column C1 by clicking the blank column label and typing "Pressure"

• Name Column C2 "Density"

• In Column C1, enter the pressure data from the x column in Table 4.1 (p. 124).

• In Column C2, enter the density data from the y column of Table 4.1.

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3. Generate the fitted line plot with confidence curves and prediction limits.

• Select "Stat --> Regression --> Fitted Line Plot."

• Fill out the resulting dialog box as follows:

Input Type Label Value
Response (Y): Density
Predictor (X): Pressure
Linear selected

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• Click "Options."

• Fill out the resulting dialog box as follows:

Input Type Label Value
Logten of Y unchecked
Logten of X unchecked
Display confidence bands checked
Display prediction bands checked
Confidence level: 95.0
Title:

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• Click "OK" to close the "Options" dialog box.

• Click "OK" in the "Fitted Line Plot" dialog box.

MINITAB displays a fitted line plot of Density vs. Pressure.

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### Section 2: Obtaining the Fitted Linear Equation and Additional Numerical Summaries

1. Display summary information for the fitted line.

• Select "Stat --> Regression --> Regression."

• Fill out the resulting dialog box as follows:

Input Type Label Value
Response: Density
Predictors: Pressure

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• Before closing the dialog box, click "Results."

• In the dialog box that follows, click the radio button next to the label, "In addition, the full table of fits and residuals."

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• Click "OK" to close the "Results" dialog box.

• Click "Options."

• Fill out the resulting dialog box as follows:

Input Type Label Value
Weights
Fit intercept checked
Variance inflation factors unchecked
Pure error unchecked
Durbin-Watson statistic unchecked
Data subsetting unchecked
PRESS and predicted R-square unchecked
Prediction intervals for new observations: 5000
Confidence level: 95
Fits unchecked
Confidence limits unchecked
SE of fits unchecked
Prediction limits unchecked

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• Click "OK" to close the "Options" dialog box.

• Click "OK" in the "Regression" dialog box.

MINITAB displays summary information, including the regression equation, a table of fits and residuals, and a predicted value for x=5000.

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