Establishing Cause and Effect from DataJason McFall, Causata

Use temporal informationCauses precede effects

Granger causality

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Does wage inflation lead to price inflation, or vice versa?

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WebsiteSession

WebsiteSession

Call CenterQuestion

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Loyalty CardSign Up

Major Product Purchase in Store

Store all the detail, in time order

filter customer journeystime

filter customer journeysalignrelative timetime

before after

Build models

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XPXW

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G

IR

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BP

Bayesian networksAnalysing observational data is hard

ExperimentPut the science into data science

INTERVENTION

CONTROL

Split population randomly into two groups

Measure outcomes for both groups

Randomised Controlled Trials

Renewal rate

vsRENEW

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virus protection

Randomise

Concurrent control

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Bandit algorithmsIncluding random exploration

confi

denti

al

response rate

Regulated exploration/exploitation

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Click on ad Acquire new customer

Retain Customer

Measure the right thing!

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Beware of bias

Beware of bias

Confirmation bias

Analysing observational data is HARD. It’s often much easier to do experiments!

Randomise

Use concurrent controls

Be alert to bias

Summary

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Thankyou