If It Fits Three Data Sets, It Describes None of Them

You'll learnwhat makes a description of a distribution complete, by testing each sentence against three data sets until only one of them still fits.

Three groups of thirty runners, three distributions, and all three have a median of exactly 50 minutes. So "centered at 50 minutes" is true of every one of them, which means it identifies none of them — and that is the whole of what an incomplete description is. Add the shape and two data sets survive. Add the variability and one does. Add the unusual features and the units and the group, and the sentence finally points at a single distribution and nobody else's. This animation runs that test literally: every candidate sentence is checked against all three data sets and the screen reports how many it still fits. Twelve short steps; press Next for each one.

12 STEPS · 6 QUICK CHECKS · SHAPE · CENTER · VARIABILITY · UNUSUAL FEATURES · IN CONTEXT · v2

Three distributions, one median of 50 — a sentence that fits 3 describes 0.

Before you start

What you're looking at

Three groups of 30 runners' times in minutes, as boxplots on one shared axis. All three have a median of exactly 50.

The question

What has to be in a sentence before it describes ONE of these three rather than all of them?

Step 1 / 12