AI engineering glossary · Classical ML algorithms

What is linear regression?

Linear regression: A supervised method that predicts a number as a weighted sum of input features plus a constant. Training picks the weights that make predictions as close as possible to the known answers, usually by minimising squared error. It is fast, easy to interpret and a standard baseline for numeric prediction.

Level: beginnerTopic: Classical ML algorithms

Linear regression: an example

Predicting a flat's monthly rent in Bengaluru as 4000 + 25 * area_sqft + 3000 * bedrooms; a 900 sqft 2-bedroom flat gives 4000 + 22500 + 6000 = 32,500 rupees.

Linear regression in Python

A short example you can run (Python 3.11, NumPy). The output below is what it really prints.

import numpy as np

sqft = np.array([500, 750, 1000, 1250, 1500])
rent = np.array([12000, 16500, 21000, 25000, 30000])     # rupees per month (made-up data)
slope, intercept = np.polyfit(sqft, rent, 1)
print(f"rent = {slope:.2f} * sqft + {intercept:.0f}")
print("predicted rent for 1100 sqft:", round(slope * 1100 + intercept))

Output

rent = 17.80 * sqft + 3100
predicted rent for 1100 sqft: 22680

Related terms

More Classical ML algorithms terms

Where you learn it

Linear regression is part of the AI Engineering Program, which teaches it with notes, a hands-on lab and an exam. The first lesson is free.

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