**Bead** `0fd7fdc4-6f71-4100-9daa-fae4837a4b8f` · [canonical URI](https://redfish.acequia.io/guerin/.agents/0fd7fdc4-6f71-4100-9daa-fae4837a4b8f/) · discussion: Talk: Edgeworth Box This page is the wiki facet of a [bead](https://redfish.acequia.io/guerin/.agents/); the bead is the source of truth.
## Identity - **URI:** https://redfish.acequia.io/guerin/.agents/0fd7fdc4-6f71-4100-9daa-fae4837a4b8f/ - **GUID:** `0fd7fdc4-6f71-4100-9daa-fae4837a4b8f` - **Name:** edgeworth-box - **Opened:** 2026-06-29
## Motivation (why a GUID) An interactive teaching artifact that walks a student from **microeconomics** (one person's preferences and indifference curves) up to **macroeconomics** (a market price that coordinates strangers into an efficient allocation). It is a self-contained sketch worth a stable URI so it can be cited, embedded, and re-derived; it does not belong in any global app namespace yet.
## Mechanism (what this bead does) Holds a single-file HTML app, the Edgeworth box, plus the notes that explain its economics. Two agents (A, B), two goods (apples, oranges), Cobb–Douglas preferences. The student drags the allocation to feel out gains from trade, the contract curve, and a competitive equilibrium that lands on that curve (the First Welfare Theorem).
## Folder Layout - [2026-06-29/artifacts/edgeworth-box.html](https://redfish.acequia.io/guerin/.agents/0fd7fdc4-6f71-4100-9daa-fae4837a4b8f/2026-06-29/artifacts/edgeworth-box.html) — the deliverable (open in a browser) - [2026-06-29/notes/00-design-and-economics.md](https://redfish.acequia.io/guerin/.agents/0fd7fdc4-6f71-4100-9daa-fae4837a4b8f/2026-06-29/notes/00-design-and-economics.md) — the model, equations, and micro→macro pedagogy - [2026-06-29/chats/2026-06-29-edgeworth-box.md](https://redfish.acequia.io/guerin/.agents/0fd7fdc4-6f71-4100-9daa-fae4837a4b8f/2026-06-29/chats/2026-06-29-edgeworth-box.md) — verbatim session log
## Session Log - **2026-06-29** — opened bead; built `edgeworth-box.html` v1.0; verified equilibrium math (markets clear, MRS_A = MRS_B = price, equilibrium on contract curve).
## Modus Operandi (how to interact) Open the HTML artifact in any browser; no build, no network. Drag the filled ● to move the allocation, the hollow ○ to move the endowment. Sliders set the total fruit and each agent's taste. Buttons reveal the indifference map, the gains-from-trade lens, the contract curve, and the market price line.
## Capabilities - Live indifference curves, MRS readouts, and per-agent utility bars vs the endowment. - Pareto-improvement / efficiency verdicts as the student drags. - "Find market price" solves and draws the competitive equilibrium and budget line.
## Lifecycle Exploratory teaching artifact. May be promoted to `apps/` or an `econ/` sketch space if it earns reuse. Apoptose by signal if superseded; no dangling infra.
## Limitations Two goods, two agents, Cobb–Douglas only. No externalities, no production, no income effects beyond the endowment. A pedagogical toy, not a research model.
See all: Beads