# 사전 지식

- **인과추론을 왜 하는가 (또는, 준실험이 왜 필요한가?)**: RCT 또는 AB 테스트를 종종 윤리적, 비용적 이유로 할 수 없을 때 합니다.
- **Some Key Concepts**
  - Python and Data Science: Data Cleaning / Preprocessing / Visualization etc.
  - Statistics and Econometrics: Hypothesis-testing(p-value, confidence interval), panel data, DAG, Bias (Confounding, Selection Bias), Moderator vs Mediator
  - Machine Learning: train-test split, cross-validation, some famous models (Regularized Regression, Logistic Regression, Random Forest, XGBoost, etc.)