Correlation and Causation Symbolsgood shorthand against bad mental shortcuts
I accidentally did myself a very good turn when it comes to taking notes. Using x→y for “x causes y” or “x implies y” but x∝y for “x correlates with y” or “x is proportional to y” helps remind me to distinguish causation and correlation.
| Symbol | Unicode | HTML Entity | Vim Digraph |
|---|---|---|---|
| → | U+9192 |
→ |
Ctrl+K -> |
| ← | U+2190 |
← |
Ctrl+K <- |
| ∝ | U+221D |
∝ |
Ctrl+K 0( |
Inverse correlations can also be expressed with ∝, as correlations to the reciprocal: x∝⅟y, x∝1/y, x∝y-1, or x∝y¹.
| Symbol | Unicode | HTML Entity | Vim Digraph |
|---|---|---|---|
| ⅟ | U+215F |
||
| ¹ | U+00B9 |
¹ |
Ctrl+K 1S |
I recall using ∴ for therefore and ∵ for because in grade school. I believe I saw those first in chemistry class. The arrows used in computer science and formal logic eventually won out in my personal shorthand.
| Symbol | Unicode | HTML Entity | Vim Digraph |
|---|---|---|---|
| ∴ | U+2234 |
∴ |
Ctrl+K .: |
| ∵ | U+2235 |
∵ |
Ctrl+K :. |
It probably helps that legible lines are easier and faster to write by hand than dots. And that the causal directions of → and ← are obvious.
Your thoughts and feedback are always welcome by e-mail.