Providing a blend of theory and application, this text emphasizes understanding concepts, which are demonstrated by means of worked-out examples. The theoretical side enables applications of regression analysis to be carried out successfully. Computer and graphic plots focus the text on analysis and models, and discussion of regression diagnostics includes the DFBETAS, DFFITS, and PRESS measures. Model building is examined in order to allow students to see how the model-building process integrates many of the elements considered in earlier chapters. This edition includes new topics, such as: robust tests for constancy of the error variance, smoothing techniques to explore the shape of the regression function, robust regression and non-parametric regression techniques.