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Data & Analytical Thinking

Column VII. Every lesson leaves you with a working thing.

LevelSort
DT-05L3"A Study Showed That…": How to Actually Read a PaperOne real paper evaluated against a six-question checklist, with a verdict you can defendDT-09L1A Four-Step Protocol for Verifying a SourceYour own four-step verification checklist, applied to three claims you actually ran into this weekDT-03L1Correlation Is Not Causation, With Real ExamplesFour real causal claims taken apart — for each, the four possible explanations tested and the most likely one namedDT-10L2Decision Frameworks: Expected Value, Reversibility, Opportunity CostOne real decision run through the frameworks: expected value estimated, reversibility and opportunity cost assessed, a defensible choice madeDT-11L3Fermi Estimation: Producing a Number When You Have No DataThree Fermi estimates worked start to finish, each with its assumptions listed and a sanity-check against realityDT-02L1How Charts Lie: Eight Manipulation TechniquesA detection list of the eight techniques, applied to three real charts found in the wildDT-12L1How the Algorithm Knows YouA before/after record of your own feed — the 20-click experiment run on a real accountDT-08L2Logical Fallacies: Where an Argument Actually BreaksTen fallacies you can name on sight, applied to three real arguments — with one of them steelmanned instead of dismissedDT-06L3p-values, Statistical Significance and Effect SizeA concept map plus one real study read for what its p-value does and doesn't claim, alongside its effect sizeDT-01L1Reading Data: Mean, Median, Spread — and the Lie of the AverageThree real datasets summarised correctly — mean, median and spread — with the misleading summary identified in eachDT-04L2Sampling, Survey Design and Why Most Surveys Are JunkA teardown of three real surveys or polls with each one's fatal flaw named, plus one leading question rewritten neutrallyDT-07L1Ten Cognitive Biases and Where You'll Meet Them TodayA diagnostic card of the ten biases, each matched to one real moment from your own last week