Concepts this paper tests
Auto-generated summary from the source site. Handy as a checklist; the lessons above explain each idea from scratch.
Summary of Core Topics, Concepts, Principles, and Equations
Linear Algebra
Matrices and Rank
- Rank of a matrix
- Column space and row space
- Upper and lower triangular matrices
- Eigenvalues and eigenvectors
- Diagonalizable matrices
Matrix Operations
- Matrix addition and multiplication
- Matrix inversion
- Projection matrices
Eigenvalues and Eigenvectors
- Calculation of eigenvalues and eigenvectors
- Properties of eigenvalues and eigenvectors
Projection Matrices
- Projection of a vector onto a line
- Properties of projection matrices
Calculus
Limits
- Evaluation of limits
- Finite and infinite limits
Continuity
- Continuous functions
- Conditions for continuity
Derivatives
- Partial derivatives
- Directional derivatives
- Linear approximation
Machine Learning
Least Squares Method
- Best-fit line
- Error vectors
Classification Models
- Misclassification error
- Sign function
Equations
Linear Algebra
- Eigenvalues and Eigenvectors
Av=λv
where A is a matrix, v is an eigenvector, and λ is an eigenvalue.
- Projection Matrix
P=aTaaaT
where a is a vector.
Calculus
- Partial Derivatives
∂x∂f,∂y∂f
for a function f(x,y).
- Directional Derivative
Duf(a,b)=∇f(a,b)⋅u
where ∇f is the gradient of f and u is a unit vector.
- Linear Approximation
L(x,y)=f(a,b)+∂x∂f(a,b)(x−a)+∂y∂f(a,b)(y−b)
Machine Learning
- Least Squares Method
y^=mx+c
where m is the slope and c is the intercept.
- Sign Function
Sign(x)={1−1if x≥0if x<0