Options, exercise and learned hedging
A practical primer: contracts, probability, financing, Greeks, exercise decisions, learning and the application tools. Worked examples and a guided reading list.
Volt calculates option prices, Greeks and portfolio exposures. Jormungandr trains and serves hedging policies. These papers document their models, application interfaces and completed experiments.
Observed option quotes and paired stock prices: 64 American contracts across eight stocks and ETFs, captured over about 24 seconds. Volt supplies exercise-aware implied volatilities and Greeks. The example book holds one long contract per row; the final browser scene edits one quantity. Carry uses a flat 4% rate, zero yield and an empty cash-dividend schedule. Playback uses presentation pacing. Raw quote files and the replay producer remain outside the public source checkout.
Bring option quotes, stock observations and contract terms into one dated calculation.
Calculate contract Greeks, signed book exposures and the effect of specified market moves.
Train a policy on financed trading paths, including the liability payment and transaction costs.
The primer covers the financial and mathematical background. The application papers document pricing methods, hedge-learning experiments and software interfaces.
A practical primer: contracts, probability, financing, Greeks, exercise decisions, learning and the application tools. Worked examples and a guided reading list.
A five-stock Bermudan contract: continuation learning, independent price estimates, the vector hedge account and measured CPU/GPU execution.
Prices, Greeks, portfolio units and CPU/GPU calculations for a call-and-put book.
The Heston market, financed trading account, loss preferences and completed hedging experiments.
The control problem and the training, evaluation and holdings-inference API calls.
Quote handling, implied volatilities, contract Greeks and portfolio scenarios in an updating risk view.
Gamma, theta, hedge frequency and transaction costs in a European straddle.
The application creates a learner and uploads separate training and validation batches. Each update advances a model version. Inference takes current observations and holdings, then returns target quantities.
Volt retains the financial calculation, tensors and optimizer in its worker. Jormungandr supplies the HTTP interface, dataset partitions, model lifecycle and checkpoints. Other compatible engines can use the same interface.
from jormungandr.client import JormungandrClient
client = JormungandrClient("http://127.0.0.1:8080")
version = client.get_native_model("hedge")["version"]
client.native_command("hedge", "update", {
"batch_id": "train", "expected_version": version})
risk = client.native_command("hedge", "evaluate", {
"batch_id": "validation"})
holdings = client.native_command("hedge", "infer", {
"step": 0, "paths": 1, "features": [0., 1.],
"previous_holdings": [0., 0.]})A European contract settles at expiry. A Bermudan holder chooses among stated exercise dates; an American holder can exercise throughout the permitted interval. The writer’s hedge must respond to the resulting cash payment or stock delivery. That timing enters the contract model, pricing method and trading account.
Becker, Cheridito and Jentzen develop learned stopping rules and dynamic hedges for these problems. Volt supplies the dated pricing reference, learned exercise policies, price-bound estimates and a writer account that settles and closes its hedge at exercise. A one-year Bermudan put study with monthly hedging reduced mean squared loss from 61.44 unhedged to 4.01 without fees and 4.08 with 10-basis-point stock fees; numerical delta reached 3.94 and 3.98. The application guide includes a runnable writer example, and the learned-stopping guide explains the two holder algorithms and interval hedging. A five-stock Bermudan max-call comparison now recovers prices 26.1576–26.1609 across three independently initialized models, against the published 26.154. Each model was assessed on 4,096,000 fresh lower-estimate paths and 2,048 nested outer paths; the reported confidence intervals are wider than the paper’s. The executed configurations and comparison record accompany the multi-asset application paper. The original studies cover direct optimal stopping and American-style pricing and hedging.