#2701: Change in Slope

XKCD comic, described below.
Transcript

How to detect a change in the slope of your data

[First column, on the left]

Novice method:

[A graph, with dots forming a rough line, math formulas, and sub graphs]

Do a bunch of statistics

[Second column, on the right]

Expert method:

[Perspective view of the previous graph, with the legend "Hey look, it bends here" and an arrow pointing to the graph]

Tip the graph sideways


(Sourced from explainxkcd.com)

Squinting at a graph is fine for getting a rough idea of the answer, but if you want to pretend to know it exactly, you need statistics.

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