**Statistics Basics**

Difference between Sample and Population

Difference between Descriptive Statistics and Inferential Statistics

**Descriptive Statistics**

Quartile: Definition and Example

Sample Variance Formula and Calculation by Hand

Population Variance Formula and Calculation by Hand

**Inferential Statistics**

Two-Way ANOVA: Formulas and Calculation by Hand

Two sample t-test: Definition, formula, and Examples

OLS vs. MLE in Linear Regression

Maximum Likelihood Estimation (MLE) in Linear Regression

Calculate Sample Size for Chi-square Test

**Linear Algebra**

Orthonormal Vectors: Definitions and Examples

Difference between Space and Subspace

Linear Regression and Orthogonal Projection