Quant Library · Match pricing · Football
Laplace Uncertainty
A band around every probability, from the curvature of the likelihood at its optimum.
The fitted parameters have a covariance: the inverse Hessian of the negative log likelihood. Draw from it, re-price, and you have a distribution over prices rather than a single number.
Inputs
3What it takes
| Name | Type | Units | Where it comes from |
|---|---|---|---|
| fit | fitted model | - | the Match Price Engine |
| matches | the weighted match list the fit used | - | the same source |
| draws optional | int | count | your choice; 400 is enough for a 90% interval |
Outputs
3What it gives back
| Name | Type | Units | Notes |
|---|---|---|---|
| covariance | k x k array | - | |
| interval | (low, high) per outcome | probability | |
| width | float | probability points | what the Predict page calls How sure |
Method
How it works
- Compute the Hessian of the weighted negative log likelihood at the optimum by central differences.
- 2 further steps in the licensed specification
Assumptions
- The likelihood is approximately quadratic near its optimum, which is the usual large-sample argument and is weakest for teams with few matches.
Limits
- It is parameter uncertainty only. It says nothing about the model being the wrong shape, which is the larger error.
- 1 further limits in the licensed specification
In the package
- The full specification: inputs, method, assumptions and limits
- The validation panel as measured on the day of purchase
- A reference implementation extracted from the running source
- Perpetual commercial use for one entity
Reference modules:
- 1 module(s), named in the licensed specification and shipped in the package
Read this before you buy. The platform's own walk-forward tests say the closing line forecasts football better than these models do. What they give you is a coherent price for every market and match, before the market opens, with the band and the working attached. Any model here that has been beaten by something simpler says so in its limits, and the validation panel above is generated from the platform's result files rather than typed in.