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Pillar VII · DT

Data & Analytical Thinking

Re-checked every 365 days12 lessons · 12 live
L1DT-01L1Reading Data: Mean, Median, Spread — and the Lie of the Average Three real datasets summarised correctly — mean, median and spread — with the misleading summary identified in each
L1DT-02L1How Charts Lie: Eight Manipulation Techniques A detection list of the eight techniques, applied to three real charts found in the wild
L1DT-03L1Correlation Is Not Causation, With Real Examples Four real causal claims taken apart — for each, the four possible explanations tested and the most likely one named
L2DT-04L2Sampling, Survey Design and Why Most Surveys Are Junk A teardown of three real surveys or polls with each one's fatal flaw named, plus one leading question rewritten neutrally
L3DT-05L3"A Study Showed That…": How to Actually Read a Paper One real paper evaluated against a six-question checklist, with a verdict you can defend
L3DT-06L3p-values, Statistical Significance and Effect Size A concept map plus one real study read for what its p-value does and doesn't claim, alongside its effect size
L1DT-07L1Ten Cognitive Biases and Where You'll Meet Them Today A diagnostic card of the ten biases, each matched to one real moment from your own last week
L2DT-08L2Logical Fallacies: Where an Argument Actually Breaks Ten fallacies you can name on sight, applied to three real arguments — with one of them steelmanned instead of dismissed
L1DT-09L1A Four-Step Protocol for Verifying a Source Your own four-step verification checklist, applied to three claims you actually ran into this week
L2DT-10L2Decision Frameworks: Expected Value, Reversibility, Opportunity Cost One real decision run through the frameworks: expected value estimated, reversibility and opportunity cost assessed, a defensible choice made
L3DT-11L3Fermi Estimation: Producing a Number When You Have No Data Three Fermi estimates worked start to finish, each with its assumptions listed and a sanity-check against reality
L1DT-12L1How the Algorithm Knows You A before/after record of your own feed — the 20-click experiment run on a real account