# Welcome to the Feynman Symbolic Regression Database!

As opposed to *linear* regression, where a dataset is fit to a *linear* function of the given input variables, *symbolic* regression tackles the much harder problem where the unknown function can correspond to *any* combination of mathematical symbols.
To facilitate development and testing of algorithms for this, this database contains 120 symbolic regression mysteries as described in the paper
*AI Feynman: a Physics-Inspired Method for Symbolic Regression*, Udrescu & Tegmark (2019),
arXiv:1905.11481.

Each regression mystery corresponds to a table of numbers,
whose rows are of the form {*x*_{1},*x*_{2},...,*y*}, where *y* = *f*(*x*_{1},*x*_{2},...); the challenge is to discover the correct symbolic expression for the mystery function *f*.
If you're eager to get started, simply download and uncompress Feynman_with_units.tar.gz below and try dicovering 100 equations from the Feynman Lectures!
If that's too easy, please try the 20 more challenging mysteries in bonus_without_units.tar.gz.
You'll find the correct answers in the spreadsheets below.
If you prefer the mysteries simplified by dimensional analysis, try the "without_units" files instead, you'll also want to download units.csv, the unit table described in the paper.

Downloadable files:
If you have questions, please contact Silviu at sudrescu@mit.edu