4/23/2009

Chapter 10: Diagnostics

“This doesn’t seem very rigorous.” – Yaowen

 

·         Identifying Outlying Y observations

o        Studentized residuals

o        Deleted residuals

o        Studentized deleted residuals

·         Identifying Outlying X observations

o        Hat matrix: Leverage

·         Identifying Influential Cases

o        DFFits

o        Cook’s Distance

o        DFBetas

o        Average Absolute Percent Difference

 

·         Multicollinearity Diagnostics

o        Informal diagnostics

o        Variance Inflation Factor

 

·         Example: Surgical unit data (Surgery-Ch10.sas)

·         Example: Bodyfat data (Bodyfat-Ch10.sas)

·         Example: Brand preference (#10.5, 10.9, 10.15)

 

For Tuesday: Read Sections 11.1 – 11.3; prepare the following problems for a Problem Session: #??.