Data Dive · Rung 3 · What's Related · 3.3

A real correlation and a nonsense one

A hundredth of a point apart.

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One

CO2 against global temperature

CO2 against global temperature, 1992-2025r = 0.937 - NOAA Mauna Loa and NASA GISTEMPtemperature anomaly, degrees CCO2, parts per millionone year1

1992-2025

r = 0.937
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Two

CO2 against exoplanets discovered

CO2 against exoplanets discovered, 1992-2025r = 0.918 - and one of these two is not physicsexoplanets discovered, cumulativeCO2, parts per millionone year1

The same years

r = 0.918
AskFrom the correlation alone, which of these is physics?
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The point

A correlation is a question, not an answer

The nonsense one is nearly as strong. It is real data, honestly plotted, and it says that humanity got better at finding planets while it got better at burning carbon.

Both numbers went up since 1992. So did a great many things.

The three questions
  1. Which of these two chose its axes to make a point?
  2. How much weaker would the second have to be before you stopped believing it -- and is that a number or a feeling?
  3. Somebody shows you r = 0.9 for a claim you already agree with. What do you ask them?
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After the dive

The shapes on this page, in the library’s own words

the scatter

Each dot is one thing measured twice. A tight cloud along a line means the two move together.

What it leaves outTwo things moving together is not one causing the other, and a third thing neither axis shows may be moving both.

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