xiv PREFACE TO THE FOURTH EDITION
and screening are also given. The remaining chapters are concentrated on statistical
techniques that are widely used in biomedical and public health research.
A short list of references is included at the end of each chapter. The object here
is to include at least one reference that would cover the material mentioned in the
chapter and also to include references that include additional information.
For the instructor who is concerned about covering the text in a single semester or
quarter, note that the chapters are short. The information on tests when the population
variance is known could be mentioned briefly, and the use of confidence limits for the
differences between two means could be omitted. These two topics are not available
in most computer programs. The chapter on survivor analysis may not be as relevant
to public health students as it is to medical researchers.
The fourth edition has benefited from the work of Amy Hendrickson
(TeXnology.com) in checking and preparing early chapters and in final versions of
the book.
I am sorry to report that Jean Dunn died in January 2008. I still regard this as her
book, as she wrote the first two editions and her clarity of thinking and thoughtful
writing is what makes this book a good choice for readers who want to understand
what they are doing.
OLIVE JEAN DUNN AND VIRGINIA A. CLARK