Although modern statistical software* includes menu-driven graphical interfaces, the programs also allow tests to be run using commands, which can be saved for future use. The command syntax style in this appendix illustrates how to generate the results used as examples in this book. In addition, for those procedures that are based on graphical interfaces, we describe the options that should be selected in the user interface to implement the analyses. These examples and notes should provide a useful practical supplement to the documentation that accompanies these programs—which can range from overwhelming to frustratingly terse—to help you apply what you learn from this book into solving practical problems.
This appendix is organized according to the primary statistical topic being illustrated (e.g., regression, multicollinearity) with subsections giving the control files for working the examples. We carry many of the examples through several chapters in the book, but when a command syntax file is provided, all the control commands necessary to generate the entire example are contained in a single file, with comments noting which part of the example is being computed at each step. Any user notes and hints are provided in context in the appropriate section of this appendix. We list which figures in the book are produced by the syntax. Some of these figures have been redrawn for clarity or emphasis, so do not look exactly the same as what the software generates but the information in them is the same.
These files, together with the input data files, are available at mhprofessional.com/appliedregression.
We include code to read the data files assuming that these files are in the default folder (path) for the statistical software. If you put the data files in a different folder, you will need to modify the statements that read the files to indicate the folder containing them. Alternatively, you can open the data files directly within the programs after you have launched them.
For SAS command syntax files, it is assumed that you have loaded the permanent SAS data set into a temporary work SAS data set using a LIBNAME statement to refer to the location of the permanent data set. For instance, if you wanted to access the data in Table C-1 in Appendix C and if you stored the data set in C:\TEMP, then one way to read the data set into SAS is:
LIBNAME mylib "C:\TEMP";