Solutions to Tutorial 6 Problems

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Presentation transcript:

Solutions to Tutorial 6 Problems 1. The matrix plot of the Milk Production Data

The linearity assumption is ok. The measurement error assumption: a). Normality: seems ok b). Mean zero: ok c). Independence: seems ok d). Homogeneity: slightly violated. The predictor assumption: a). Nonrandom: violated b). No measurement errors: unknown c). Linearly independence: not violated. 4. The observation assumption: violated. There are some outliers.

The matrix plot of the Right-to Walk Laws Data

The linearity assumption is ok. The measurement error assumption: a). Normality: seems violated b). Mean zero: ok c). Independence: seems ok d). Homogeneity: slightly violated. The predictor assumption: a). Nonrandom: violated b). No measurement errors: unknown c). Linearly independence: not violated. 4. The observation assumption: seems violated. There are 3 outliers.

The matrix plot of the Egyptian Skulls Data

The linearity assumption seems violated. All other assumptions can not be checked.

The matrix plot of the Domestic Immigration Data

The linearity assumption is ok. The measurement error assumption: a). Normality: seems ok b). Mean zero: ok c). Independence: seems ok d). Homogeneity: seems ok. The predictor assumption: a). Nonrandom: violated b). No measurement errors: unknown c). Linearly independence: not violated. 4. The observation assumption: seems violated. There are outliers.

The matrix plot of the New York Rivers Data

The linearity assumption is ok. The measurement error assumption: a). Normality: seems violated b). Mean zero: ok c). Independence: seems ok d). Homogeneity: seems ok. The predictor assumption: a). Nonrandom: unknown b). No measurement errors: unknown c). Linearly independence: not violated. 4. The observation assumption: seems violated. There are some outliers.

Assumptions Violated: 1). The Linearity Assumption is violated 2. a) The SLR fit results in the following: The regression equation is Minutes = 37.2127 + 9.96950 Units S = 18.7534 R-Sq = 89.7 % R-Sq(adj) = 89.2 % Analysis of Variance Source DF SS MS F P Regression 1 67084.8 67084.8 190.749 0.000 Error 22 7737.2 351.7 Total 23 74822.0 Assumptions Violated: 1). The Linearity Assumption is violated 2). All other Assumptions can not be checked since linearity is violated.