Expected Shortfall

Lesson Overview

In "Quant Risk Framework" → "VaR 框架", this lesson "Expected Shortfall" builds knowledge you can apply immediately.

ES描述规定尾部的平均损失。有限样本下“严格超过VaR”与“取最坏k项”可能不同，重复分位值时尤须写清约定。 与VaR同损失号和持有期→声明尾部集合→计算均值→列重复值和小样本限制→不混用定义。 本课作业：对上一组10项损失，本课定义90%ES取最坏ceil(10%×10)=1项。ES多少？

Core Concepts

These points align with the video walkthrough—take notes as you watch.

• ▸ES描述规定尾部的平均损失。有限样本下“严格超过VaR”与“取最坏k项”可能不同，重复分位值时尤须写清约定。
• ▸与VaR同损失号和持有期→声明尾部集合→计算均值→列重复值和小样本限制→不混用定义。
• ▸本课作业：对上一组10项损失，本课定义90%ES取最坏ceil(10%×10)=1项。ES多少？

Practical Application

After studying, complete the companion practice lesson to move from understanding to doing.

• ▸Follow along in Jupyter or VS Code
• ▸Log how parameter changes affect backtest results
• ▸Submit a reproducible analysis notebook

FAQ

• ▸Q: How does this lesson fit the course? A: Part of "VaR 框架"—follow the curriculum order.
• ▸Q: What do I need? A: Demo account and notes; quant lessons need a Python environment.
• ▸Q: How do I know I've mastered it? A: Pass the quiz and explain three key points of Expected Shortfall on your own.