Irrational Exuberance (book) Irrational Exuberance (book) Irrational Exuberance is a March 2000 book written by American economist Robert J. Shiller, a Yale University professor and 2013 Nobel Prize winner. The book examines economic bubbles in the 1990s and early 2000s, and is named after Federal Reserve Chairman Alan Greenspan's famed "irrational exuberance" quote warning of such a possible bubble in 1996. Published at the height of the dot-com boom, the text put forth several arguments demonstrating how the stock markets were overvalued at the time. The stock market collapse of 2000 happened the exact month of the book's publication. The second edition of
Proof that e is irrational 1. For all terms with we have the upper estimate This inequality is strict for every "n" ≥ "b" + 2. Changing the index of summation to "k" = "n" – "b" and using the formula for the infinite geometric series, we obtain Since there is no integer strictly between 0 and 1, we have reached a contradiction, and so "e" must be irrational. Q.E.D. Another proof can be obtained from the previous one by noting that and this inequality is equivalent to the assertion that "bx" < 1. This is impossible, of course, since "b" and "x" are natural