Dale Napier writer Tai Chi Chuan Tai Chi In Your Life Queen Joan politics martial arts cyberwar
Dale Napier writer Tai Chi Chuan Tai Chi In Your Life Queen Joan politics martial arts cyberwar
Dale Napier Writer Main Blog Dale Napier Writer Writings Readings Cyber Tai Chi
Superforecasting: The Art and Science of Prediction

17 Nov 2015

Superforecasting: The Art and Science of Prediction
by Philip E. Tetlock and Dan Gardner (2015)
What is the likelihood that Donald Trump will be elected president next November? This is the test question I contrived in order to examine my understanding of this book, which demonstrates how the world's best "superforecasters" use numeric and non-numeric techniques to produce results that are often strikingly accurate.

A good deal of the book is based on Tetlock's multi-year Good Judgment Project, which seeks to discover who makes the best forecasts and under what circumstances. One interesting result, which might well be applied to a judgment of Ben Carson's bid for president, is that experts forecast quite poorly when venturing outside their areas of expertise. Non-experts seem to fare far better because, out of awareness for their lack of expertise, they dig deeper and more thoroughly to challenge pre-conceived notions and conventional wisdom. Teams do even better when the members are diverse enough to provide complementary skill sets.

Much of the numeracy is based on a sound understanding of probability, in particular Bayes' Theorem, which allows us to parcel a probability computation into manageable pieces. For instance, take my test question. The first thing we know is that in order to be elected president, Trump must receive the Republican nomination. Thus his chance of being elected president is equal to his chance of receiving the nomination, multiplied by his chance of winning the fall election.

But the chance of his winning the fall election depends on his opponent; for simplicity we will treat it as a purely Democrat-Republican contest. So Trump's chance of winning in the fall is equal to the sum of these three numbers: the probability of Clinton receiving the nomination multiplied by the probability of beating Clinton; the probability of Sanders receiving the nomination multiplied by the probability of beating Sanders; and the probability of O'Malley receiving the nomination multiplied by the probability of beating O'Malley.

If you compute the same probability for a Democrat it is messier because there are so many more Republican candidates to account for, but the principle remains the same. Tetlock maintains that many of the best forecasters do not necessarily make explicit computations, as I have for the leading presidential candidates, but they are familiar with the principles and take them into account.

The book has powerful implications for those who wish to learn to tighten their predictions, to question their assumptions and to measure results. How do you test predictions? How do you measure them? Although the book is all about numbers and how they are used, it is light on number crunching; most data is represented graphically, and I recall finding only one equation, which demonstrates Bayes' Theorem, a perfect lead-in for my test question.

You can measure my progress on the question at http://www.dalesdemocracy.com, which I expanded to include the top six presidential candidates; there is insufficient data to cover more. And true to the superforecasters' best practices, I am adjusting the data and the methodology as the campaign progresses. But don't wait to see how close my predictions get to the final results--read the book and make up your own test question. Three and a half stars.

You may also like this related article: Flash Boys, by Michael Lewis (2014) (3)
All Blogs
More Books blogs:
17 Jul 2016 Books The Paranoid Style in American Politics
26 Jun 2016 Books Book Review - Heart of Europe
30 May 2016 Books How Round Is the World?
18 Mar 2016 Books Perry Mason Meets James Bond
1 Jan 2016 Books Books in Review 2015
25 Oct 2015 Books Book Review - The Consultant
13 Aug 2015 Books Infinitesimal
2 Jul 2015 Books The Great Zoo of China
6 Jun 2015 Books The Innovators, by Walter Isaacson (2014)
15 May 2015 Books Clinton Cash Redux
10 May 2015 Books Clinton Cash
18 Apr 2015 Books Man's Search for Meaning
8 Feb 2015 Books Golden Son
23 Jan 2015 Books A Mad Catastrophe
14 Dec 2014 Books Sci-Fi Book Notes
23 Oct 2014 Books Heinlein, Scientology, and Star Trek
6 May 2014 Books Six Amendments, by John Paul Stevens (2014)
24 Apr 2014 Books Flash Boys, by Michael Lewis (2014)
13 Feb 2014 Books Double Down: Game Change 2012
23 Feb 2013 Books The Future, by Al Gore (2013)
More Blog Categories:
Boulder City (10)
Culture (24)
Culture/TV (3)
Cyber (1)
Cyber / Military (2)
Energy/Environment (3)
Health & Fitness (4)
Money (1)
Politics (10)
Science (3)
Tai Chi (111)
Writing (4)