カテゴリー 全て - judgement - forecasting - ecosystems - theories

によって Paweł Badeński 12年前.

547

Why Foxes Are Better Forecasters Than Hedgehogs

In the realm of political forecasting, two archetypes emerge: foxes and hedgehogs. Hedgehogs approach the world through a single, overarching theory, extending their ideas across multiple domains with confidence and parsimony.

Why Foxes Are Better Forecasters Than Hedgehogs

Why Foxes Are Better Forecasters Than Hedgehogs

Aggregate of experts do better than single experts

Experts won with their students

Hedgehog-Fox Ecosystems

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

Foxes vs hedgehogs

Mindless competition
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."
Diffident about their ability to forecast
Skeptical of grand theories
Ideal-type hedgehog - "relate everything to a single central vision, ...in terms of which all that the say has significance"
Confident in their forecasting ability
Extend their theory into many domains
Parsimony

Two aspects of accuracy

Discrimination
perfect = 100%
Calibration
perfect = ZERO

Benchmarks

Do you know what you do and do not know
Scrutinize mental process
Keeping track of your guesses
Meta-knowledge indicators
Knowledge indicators

Prediction markets

Probability and humans

if you use complex statistical models virtuall all experts loose
People listen when you say 1 or you say 0
"Humans can only distingiush three levels of probability: impossible, maybe, inevitable", Amos Tversky
not linear

What do hedgehogs do well

Blak Swans
Assign higher probabilities to big changes that do materialize (but at steep cost in false-positive predictions)
Which makes them more interesting ;)

An 18-year Research Project

Good predictor is - How you think!
"Foxes" beat "hedgehogs"
Traditional divisions of opinion have little weight
optimistiv vs pessimistic
liberals vs conservatives
predictions pass clarvoyance test
28 000 forecasts
12 years average work experience
Almost all had post-graduate training
284 area experts

Russian-American tension - comittee

similar predictions with war in Iraq
then gorbachov comes
OLIS - outcome-irrelevant situation
usual NRC due dilligence
rather conservative predictions

Good political judgement