Linear Regression from Scratch
Single and multivariable linear regression built from first principles using only NumPy.
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Key Metrics
0
External ML Libraries
NumPy
Only Dependency
2
Implementations (Single + Multi)
Matrix
Solution Method
Approach
Technical Overview
Normal Equation
The closed-form solution β = (XᵀX)⁻¹Xᵀy was implemented directly using NumPy matrix operations. This gives the exact least-squares solution and requires a solid grasp of linear algebra — matrix transposition, inversion, and the geometric interpretation of orthogonal projection.
Gradient Descent
An iterative gradient descent implementation was also built, updating weights by the gradient of the mean squared error at each step. This implementation handles the learning rate, convergence criteria, and loss history tracking that practitioners deal with when closed-form solutions are computationally infeasible.
Why This Matters for Quant Work
Linear regression is the foundation of factor models, risk attribution, and a large portion of quantitative strategy research. Building it from scratch demonstrates that the mathematical mechanics are understood — not just the sklearn API call. Every regularization technique, covariance estimate, and OLS assumption traces back to this foundation.
Gallery
Output & Visualizations
Demo screenshots and output visualizations — coming soon.




Single Variable Regression Fit — Observed data, fitted line, and true line
Residual Analysis — Residuals vs. predicted values for multivariate model
Actual vs. Predicted — Multivariate regression prediction accuracy
Estimated Coefficients — Bar chart of fitted regression coefficients
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