Lay D’Alembert Staking Plan
Overview
The D’Alembert system adapted for lay betting. Increase liability by 1 unit after a losing lay, decrease by 1 unit after a winning lay. The moderate linear progression makes it one of the safer negative progression options for lay betting.
How It Works
- Start with a base liability unit
- Lose lay (selection wins): Increase liability by 1 unit
- Win lay (selection loses): Decrease liability by 1 unit (never below base)
- Theory: over time, wins and losses balance, each pair producing +1 unit profit
Formula
\[L_{i+1} = \begin{cases} L_i + 1 & \text{if lay lost (selection won)} \\ \max(L_i - 1, L_0) & \text{if lay won (selection lost)} \end{cases}\]Where $L_i$ is the liability for bet $i$, measured in units.
Parameters
| Parameter | Type | Default | Description |
|---|---|---|---|
base_liability |
number | 1 | Starting liability (units) |
increment |
number | 1 | Units to increase/decrease |
Risk Assessment
- Risk Level: Medium
- Max Drawdown: Linear — 10 consecutive losing lays = 55 units lost
- Recommended Bankroll: 100–200 units
⚠️ Lay-Specific Warning
D’Alembert for lay betting escalates liability, not stake. Each additional unit of liability at odds of 5.0 means the stake only increases by 0.25 units — but the financial risk is explicit and controlled. This makes lay D’Alembert safer than back D’Alembert at equivalent unit sizing, because you control the liability directly.
Betfair Exchange Notes
- Use liability-based D’Alembert (not stake-based) for predictable risk
- At short lay odds, liability and stake are similar; at long odds, stake is much smaller than liability
Related Plans
- D’Alembert — Back betting original
- Lay Ladder — Structured lay progression
- Incremental Loss Recovery — Similar linear approach
Sources
- Plan source: MarketFeeder — Lay D’Alembert
- Plan mechanics: Mathematical formulas and plan concepts are in the public domain