# Simple regression from moments

> ML preparation item.

- Stable ID: `original-stats-regression`
- Area: Mathematics
- Topic: Statistics
- Origin: original
- Expected time: 7 minutes
- Skills: covariance-estimation, simple-linear-regression, maximum-likelihood
- Item JSON: https://mlprep.iwase.dev/data/items/original-stats-regression.json

## Problem

In simple linear regression with an intercept, $\operatorname{Var}(X)=4$ and $\operatorname{Cov}(X,Y)=6$. Find the population least-squares slope. If $\mathbb{E}[X]=2$ and $\mathbb{E}[Y]=5$, find the intercept.


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