好书，考虑到弟兄们的经济状况，是否可以打个折？

i used the 1st ed of this book in an actuarial course. 1st is not really good, as it ommitted lots of steps and some contents differ the way in traditional framework.And if you look at the book's website, heaps of typos in the 1st edition.

1st edition is better for graduate student who are already familiar with these concepts.

I hope the 2nd edition would be getting better.

Thx for you to provide it.

真是好书！

楼主太好了，谢谢