I had read the 3rd edition when I decided to use this textbook for teaching purpose this year. However, having ordered the fourth copy, I am quite disappointed at all the material that has been cut out of this book. The previous edition, even though longer, made a lot more sense and was much better. This paper quality of this edition is also awful (adding tons of weight to the book). The accompanying website does not provide much help in terms of additional resources. Would be very happy if the 3rd edition was updated (but not reduced as this edition).