This book is a combination of the basic theory of Econometrics with examples, exercises, and instructions for using programs on a computer. As it aims to help the reader use systematically the appropriate econometric methods to identify any problems in various research efforts, it encourages the use of programs for proper and complete analysis. Special emphasis is given to the instructions for using the programs EVIEWS, MINITAB, SPSS, and the EXCEL worksheet in detail in each chapter. If after reading the book and learning the covered topics, we are able to identify and eliminate existing sampling problems, then the book will have achieved its purpose.