Why Foxes Are Better Forecasters Than Hedgehogs

Good political judgement

Russian-American tension - comittee

rather conservative predictions

usual NRC due dilligence

then gorbachov comes

OLIS - outcome-irrelevant situation

similar predictions with war in Iraq

An 18-year Research Project

284 area experts

Almost all had post-graduate training

12 years average work experience

28 000 forecasts

predictions pass clarvoyance test

Traditional divisions of opinion have little weight

liberals vs conservatives

optimistiv vs pessimistic

Good predictor is - How you think!

"Foxes" beat "hedgehogs"

What do hedgehogs do well

Assign higher probabilities to big changes that do materialize (but at steep cost in false-positive predictions)

Which makes them more interesting ;)

Blak Swans

Probability and humans

not linear

"Humans can only distingiush three levels of probability: impossible, maybe, inevitable", Amos Tversky

People listen when you say 1 or you say 0

if you use complex statistical models virtuall all experts loose

Prediction markets

Benchmarks

Knowledge indicators

Meta-knowledge indicators

Do you know what you do and do not know

Keeping track of your guesses

Scrutinize mental process

Two aspects of accuracy

Calibration

perfect = ZERO

Discrimination

perfect = 100%

Foxes vs hedgehogs

Ideal-type hedgehog - "relate everything to a single central vision, ...in terms of which all that the say has significance"

Parsimony

Extend their theory into many domains

Confident in their forecasting ability

Ideal-type foxes - "pursue many ends, often unrelated and even contradictory, ... entertain ideas that are centrifugal rather than centripetal; ...without seeking them to fit them into, or exclude them from, any one all-embracing inner vision."

Skeptical of grand theories

Diffident about their ability to forecast

Mindless competition

Hedgehog-Fox Ecosystems

Hedgehogs push big ideas as far as reasonable-and often beyond

Foxes pick bits and pieces of big hedgehog ideas-and create eclectic mish-mashes that, on average, have more predictive power than the original ideas

Experts won with their students

Aggregate of experts do better than single experts