Configuring a Model
Open a model from Models in the dashboard to reach its detail page. The Configuration tab has two parts: Behaviour, which tunes how ratings move, and Match setup, the read-only shape you set when you created the model.
Behaviour has plain-language controls up top and the raw rating parameters below. Edit either, then Save (the button in the page header) to persist.
Behaviour
| Control | Options | What it does |
|---|---|---|
| New player settling speed | Slow · Medium · Fast | How fast a brand-new player's rating converges from its starting uncertainty. |
| Rating volatility | Low · Medium · High | How much a rating can move per match. Higher means bigger swings; lower means steadier ratings. |
| Team credit sharing | Winner takes most · Weighted · Even split | How a team result is split among its players. |
New player settling speed and Team credit sharing are saved on the model but do not yet affect scoring. They are placeholders for upcoming behaviour. The dashboard marks both with "Saved on the model, but not applied yet." Everything else here is applied: rating volatility and the advanced μ / σ / β parameters below.
Advanced parameters (μ / σ / β)
These are the raw rating values the plain-language controls sit on top of. Edit them directly for fine control.
| Parameter | Default | What it does |
|---|---|---|
| Mu μ | 25 | The starting skill estimate given to a player with no rating yet. |
| Sigma σ | 8.333333 | The starting uncertainty for a new player. Shrinks as they play. |
| Beta (× sigma) | 0.5 | The skill-class width, stored as a multiple of σ. 0.5 is the default (σ/2). Lower = faster, stricter rating moves; higher = slower, looser. |
| Limit Sigma | Enabled | Caps how much σ can grow back over time, keeping settled ratings stable. |
Effective beta. Because β is stored as a multiple of σ, the value sent to the
engine is β × σ. With the defaults (β = 0.5, σ ≈ 8.33) the effective β is about
4.17. The panel shows this live as you type.
The editor warns when σ drifts far from μ / 3. The default values (25 and 8.33) follow that ratio, and staying close to it keeps ratings well-scaled. Change it only if you know why.
What changes when you edit
Edits are not retroactive. They shape future ratings, not past ones.
| You change… | Effect |
|---|---|
| μ / σ | Applies only to players who have no rating yet. Players who already have a rating keep it. |
| Beta, Rating volatility, Limit Sigma | Applies to the next reported match. Every rating update from then on uses the new values. |
| Match setup (teams, players, format, scoring) | Not editable here. It is fixed at creation, so create a new model for a different shape. |
Next
- Using a Model with a Matchmaker: attach the model so tickets carry its ratings.
- Reporting Match Results: feed results back so these settings take effect.