This is probably the most disappointing university text book that I have ever bought. Its informal style may appeal to some, but too often, it simplifies the topic so much, that you don't really learn anything. On our first day, our professor said that he "hated this book but was obliged to use it." I tried to give it a chance. The formulas are not presented until the end of the chapter, and there are very few examples given, leaving the reader to try the exercises blindly. I'm sure there are better statistics texts out there.