Skip to content
Math · Statistics & data literacy

Data Detective

Spin a real dataset in 3D, drag a line to fit the points, catch misleading charts, and test whether a result is just chance.

Start lesson 1Practice exam
Live labLessons29
Loading 3D lab…
First lesson01 · A question data can answerSee all 29 lessons →

Report a mistake

What is wrong?
0 / 2000 · at least 10 characters
Sent along with your report
  • Page
  • About Data Detective · data
Plus your browser type. Reports go to our support system; see the privacy notice.
The course

7 worlds · 29 lessons

World 1 · Ask a Question, Collect Data

FREEFrom a question to a clean table
  1. 01A question data can answerStatistical questions and variables · 12 min
  2. 02Everyone or some?Population and sample · 13 min
  3. 03Watch or intervene?Observational studies and experiments · 13 min
  4. 04Tidy tables and missing valuesCleaning before counting · 13 min

World 2 · Pictures of Data

PROBars, histograms, boxes, dots and clouds
  1. 01Counts and shapesBar charts and histograms · 13 minPRO
  2. 02Five numbersDot plots and box plots · 14 minPRO
  3. 03Two numbers at onceScatterplots and the 3D cloud · 14 minPRO
  4. 04Choosing the right chartFrom question to picture · 12 minPRO

World 3 · Spread and Center

PROTypical values, odd values and how much data varies
  1. 01The typical valueMean, median and mode · 13 minPRO
  2. 02One odd valueOutliers and robustness · 13 minPRO
  3. 03How spread out?Range, IQR and standard deviation · 15 minPRO
  4. 04Compare apples to applesStandardizing with z-scores · 13 minPRO

World 4 · Fit a Line

PROCorrelation, least squares and the limits of prediction
  1. 01Does one go with the other?Correlation · 14 minPRO
  2. 02The best straight lineLeast squares · 15 minPRO
  3. 03What the line leaves behindResiduals and Anscombe's quartet · 15 minPRO
  4. 04Predict, but carefullyExtrapolation and regression to the mean · 14 minPRO

World 5 · Correlation Is Not Causation

PROHidden third factors, backwards arrows and a paradox
  1. 01The hidden third thingConfounders · 14 minPRO
  2. 02Which way does the arrow point?Reverse causation and coincidence · 14 minPRO
  3. 03Making the groups equalRandomized experiments · 14 minPRO
  4. 04Right in every group, wrong overallSimpson's paradox · 15 minPRO

World 6 · Who Asked? Sampling and Graphs That Lie

PROBiased samples, margins of error and misleading pictures
  1. 01The wrong crowdBiased samples · 14 minPRO
  2. 022.4 million answers and still wrongThe 1936 poll · 14 minPRO
  3. 03How sure can a poll be?Margin of error · 14 minPRO
  4. 04The axis trickTruncated axes and distorted areas · 14 minPRO
  5. 05Reading charts like a detectiveCherry-picking and a checklist · 15 minPRO

World 7 · Is It Just Chance?

PROSimulating luck, p-values and honest conclusions
  1. 01Luck looks lumpyChance variation · 13 minPRO
  2. 02How surprising is this?p-values by simulation · 15 minPRO
  3. 03Fishing for significanceMultiple tests and p-hacking · 14 minPRO
  4. 04How big and how sure?Effect size and bootstrap intervals · 16 minPRO
Data Detective — interactive 3D lab · Novareka