Varying position size by how strong the setup is, usually within a capped range like half to double a standard unit.
Conviction sizing tiers trades: a C setup gets 0.5 units, a B setup 1 unit, an A setup 2 units. In principle this is correct, since expected value is not constant across setups and the kelly-criterion says size should follow edge.
In practice it is where most discretionary risk discipline dies. Conviction is felt, not measured, and it correlates with recent results, market noise and mood rather than with actual edge. The A-plus trade that deserves double size tends to appear right after three winners, which is also when overconfidence peaks.
If you use it, make the tiers rule-based and narrow. Define in advance what an A setup is, cap the top tier at twice the base unit, and check the trading-journal after 100 trades: if A trades do not show a materially higher average r-multiple than B trades, your conviction has no information in it and you should size flat.
Original diagrams for the ideas on this page. Illustrative, not real market data.
Expectancy: the average trade. Forty trades sorted by outcome: 24 small losses and 16 larger wins. Weighting each side by how often it happens gives the average result per trade, marked here by the dashed line at +$120.Working out a position size. Three numbers decide how big a trade is: the account, the share of it put at risk, and the distance from entry to stop. One percent of $25,000 is a $250 budget, and a $0.50 stop divides into that 500 times.
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