Evidence Academy

Risk and position size

The part of trading that is arithmetic rather than opinion — and the only part you control completely.

Foundation6 chapters · 40 min · the whole curriculum

What risk actually is, how to size a position backwards from it, why a fixed percentage behaves so differently from a fixed lot, and how a daily limit stops a bad day becoming a bad month.

Chapters

1 Risk is an amount, not a lot size

6 min · Risk = stop distance × value per unit × size. Only size is freely yours.

2 Sizing backwards from the loss you accept

7 min · Size = accepted loss ÷ stop distance ÷ value per unit. Compute it before the ticket.

3 What a losing run actually does to an account

8 min · Losing runs are expected behaviour, not evidence the method broke.

4 The stop belongs to the idea

6 min · The stop marks where the idea is wrong, not what you can afford.

5 The daily limit and the stop-trading rule

6 min · Per-trade risk controls one outcome; a daily limit controls the sequence.

6 Prop accounts: someone else’s rules, the same arithmetic

7 min · Prop rules are the same three constraints with harder consequences.

This chapter, measured against your own trades

In the app the same chapter ends in your figures rather than an example: how often you did the thing it describes, over your last ninety days. You pick one change to make, and Evidence checks afterwards whether it actually changed — from your journal, arithmetic, no opinion involved. Questions you get wrong come back a week later and again a month after that.

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