This book is written with aim of bringing to a wider spectrum of readers, to the role of probit and binary digits in descriptive, multiple statistics and other aspects of regression techniques. Therefore, it is intended to meet the interest of, not only undergraduates and graduates students in statistics and related disciplines but also to meet the interest of practicing statisticians, research consultants and others who are interested in the use of these principles in research and practice. It is the author’s hope that readers will find this textbook an invaluable comparison.