37 Session 28: Split Track — Private Credit Case / GE Equilibrium Existence
| Unit | 5 — Split Track |
| Track 1 source | Class 23 (Private Credit Spread Decomposition) |
| Track 2 source | Class 17 (GE Market Clearing) |
37.1 Track 1: Private Credit Case Workshop
37.1.1 Track 1 Learning Objectives
By the end of this session, Track 1 students will be able to:
- Apply GE-LAV to a private credit / direct lending position.
- Decompose private credit spreads into credit risk, illiquidity premium, and complexity premium components.
- Distinguish GE-LAV for credit vs. equity strategies (cash flow profile, default risk interaction).
- Compute liquidity-adjusted spread expectations for a direct lending strategy.
- Evaluate a real BDC (business development company) or middle-market direct lending fund.
37.1.2 Track 1 Pre-Class Assignment
- Read: Recent BDC quarterly report or direct lending fund presentation
- Watch: 10-min video on private credit market structure (link on course site)
37.1.3 Track 1 In-Class Outline (75 minutes)
| Time | Segment | Format |
|---|---|---|
| 0:00–0:10 | Private credit vs. PE: structural differences | Lecture |
| 0:10–0:30 | Decomposing private credit spreads | Lecture + worked example |
| 0:30–0:55 | Lab: value a BDC or middle-market direct lending position | Group work |
| 0:55–1:15 | Group recommendations + risk implications | Presentations |
37.2 Track 2: GE Equilibrium Existence Proof
37.2.1 Track 2 Learning Objectives
By the end of this session, Track 2 students will be able to:
- State and prove the existence of GE-LAV competitive equilibrium (Theorem 17.4).
- Apply Schauder’s fixed-point theorem to the market-clearing map.
- Identify the market clearing condition mathematically: aggregate supply = aggregate demand for liquidity.
- Distinguish partial equilibrium (LAV) from general equilibrium (GE-LAV) at the level of the underlying math.
- Connect the existence proof to the calibrated parameter regime where uniqueness holds.
37.2.2 Track 2 Pre-Class Assignment
- Read: Book Chapter 17 in full (with all proofs)
- Pre-read: Mas-Colell, The Theory of General Economic Equilibrium, Chapters 4-5
37.2.3 Track 2 In-Class Outline (75 minutes)
| Time | Segment | Format |
|---|---|---|
| 0:00–0:10 | Recap: from MFG to GE | Lecture |
| 0:10–0:30 | The GE-LAV equilibrium definition | Lecture |
| 0:30–0:50 | Existence proof via Schauder | Lecture + board |
| 0:50–1:05 | Uniqueness under stability | Lecture |
| 1:05–1:15 | Numerical verification | Discussion |
37.2.4 Track 2 Discussion Questions
- The existence proof requires that \(\Psi\) is continuous on \(\mathcal{M}\). What kind of discontinuity could break this? When would discontinuity be economically realistic (e.g., regulatory thresholds, IPS triggers)?
- Under the stability condition \(\kappa > \gamma \cdot \text{Lip}(\phi)\), uniqueness holds. If the condition fails temporarily during a stress event but is restored as conditions normalize, what does the system look like during the failure period?
- The market clearing condition treats sellers and buyers symmetrically. In real markets, intermediaries (brokers) take spread. How would the proof change if we added market makers?