Sigma
50312Launch
Live on ShannonChain 50312

Sigma

The fair-value layer for dreamDEX Event Contracts on Somnia. On-chain volatility, closed-form pricing, real-time edge detection.

Φ(d₂) = fair probability · Edge = fair − book · Kelly = optimal size · All on-chain

Open Edge RadarVerify on-chain
0
On-chain Samples
0
Deployed Contracts
0
Hardhat Tests
0+
Avg Edge (bps)
0%
Student-t Improvement
$0
BTC Spot Price
Live Volatility Feed

On-chain EWMA σ — continuously updating.

σ = 0.0012samples: 428$78,054 VOL OK
Data Flow

End-to-end on-chain pipeline.

Price events flow in. Fair value flows out. No API. No keeper. No off-chain dependency.

01

dreamDEX

MarkPriceUpdated

02

RealizedVol

EWMA σ on-chain

03

SigmaOracle

Φ(d₂) fair value

04

Edge Radar

Reads fair value

The Problem

Prediction markets price blind.

No fair probability exists

dreamDEX's ec-maker quotes around fair probability — but nothing in the kit supplies that number.

Book prices are guesswork

Displayed odds are promises, not proofs. The market maker can change the price the moment you need it.

Volatility is off-chain

Realized vol lives in spreadsheets. No on-chain source exists for smart contracts to consume.

The Solution

On-chain vol → closed-form pricing → edge signal.

On-chain volatility feed

RealizedVol accumulates EWMA σ from dreamDEX MarkPriceUpdated events. 428 real BTC observations.

Closed-form pricing

SigmaOracle computes Φ(d₂) — Black-Scholes fair probability — entirely on-chain.

Edge detection

Fair probability minus book price = edge in basis points. Kelly fraction for optimal sizing.

The core math
d₂ = ln(S / S₀) + ½σ²τ / σ√τ
Fair probability = Φ(d₂)

σ from on-chain EWMA · τ from window metadata · S₀ from registry · Everything on-chain

Backtest Calibration

3,000 BTC minute candles.

Bars = predicted frequency. Line = realised. Watch the pulse track calibration.

Realised Predicted Live pulse
0
14%0%+14%
1
22%6%+16%
2
31%20%+11%
3
36%32%+4%
4
42%41%+1%
5
41%50%-9%
6
51%60%-8%
7
61%72%-11%
8
77%89%-13%
9
92%100%-8%

Gaussian Model

Brier score0.2071
Log loss0.7426

Student-t (ν ≈ 5.2) ✦

Brier score0.2007 (-3.1%)
Log loss0.5898 (-20.6%)
On-Chain Proofs

Every number is verifiable.

Click any transaction. No wallets needed. No trust required.

Price Push — $78,054
BTC price recorded on-chain via RealizedVol.recordPrice
Writer Authorization
setWriter — deployer wallet authorized for price feed
Funded Bot Wallet
25 STT transferred from Bot to Deployer for gas
RealizedVol Deploy
Contract deployment — 11.7M gas
SigmaOracle Deploy
Fair-value oracle deployment — 21.1M gas
Deployed Contracts

5 contracts live on Shannon.

RealizedVol
On-chain EWMA volatility accumulator
0xbd7e...62ef
SigmaOracle
Fair-value oracle: Φ(d₂) edge, kelly, break-even
0xe4c7...2270
SigmaWindowRegistry
Window metadata: opening price, expiry, interval
0x16b9...6731
SigmaCron
Window boundary scheduler
0xc573...a0e7
SigmaReactiveVol
Reactive volatility delivery wrapper
0x5f6a...3d28

The edge is on-chain.

5 contracts deployed. 428 volatility samples. Fair probability computed in Solidity.

Open Edge Radar View Source