He applied the "Page 99 Test" to his book, Why Does My Dog Act That Way?: A Complete Guide to Your Dog's Personality, and reported the following:
Why Does My Dog Act That Way? is a book about the personality and temperament of dogs. It covers a broad range of topics including how to test your dog’s personality, how a dog’s early experience can change its personality, how breeding can create better dogs or even “devil dogs,” and also a unique analysis of more than a thousand cases of canine heroes – namely dogs that have saved human lives. An important part of the book has to do with recently declassified data from the U.S. Army’s “Superdog” Program, and how you can apply some similar techniques to create a more intelligent, sociable and obedient dogs of your own.Read an excerpt from Why Does My Dog Act That Way? and learn more about the author and his work at Stanley Coren's website.
Page 99 of the book is a transition point in a chapter about personality testing for dogs. It is at the end of a description of an afternoon in which I took my Flat Coated Retriever, Odin, through a version of the “Canine Mentality Test” which is used to assess service and protection dogs. The test proved that Odin, although courageous and unflappable, would have made a rotten protection dog because he was simply too friendly and sociable -- even when threatened. The results of Odin’s test serve as a launch pad for a discussion of the nature of canine personality and some recent scientific findings which have tried to compare the personality of dogs to the personality of humans, ultimately concluding that although a psychologist can see similarities there are some major differences that are important.
The nature of a dog’s personality includes some of the same behavioral predispositions that we find when we analyze human personality. However, in some ways it is much simpler. Dogs have the basic emotions, such as fear, anger, joy, surprise and so forth, but none of the later learned emotions, such as guilt. Overall, dogs have a mind that is equivalent to a human two or two and half year old child, with the social consciousness of human teenager (with concerns about sex and how they fit into their social group). The bottom line, however, is that dogs do have personalities. These are predictable in part from the dog’s genetic nature as shown by his breed and in part from its individual history. Dogs are not four-footed people in fur coats, but they are also not unfeeling biological machines.
See Stanley Coren's list of the five best books about dogs.