Worked example
- Exact event probability
- 34.1158%
- Example estimate
- 40.0000%
- Decision score
- 99.6538 / 100
For at least one ace in five cards, the exact probability is 34.1158%. An estimate of 40% produces a decision score of 100 × [1 − (0.40 − 0.341158…)²] = 99.6538. The random card outcome does not change this decision score.
Example inputs
- N:
52 - K:
4 - n:
5 - k:
1 - estimate:
0.4
How scoring works
Card Odds compares your estimate with the exact hypergeometric probability. Squared probability error is the expected Brier regret; score is 100 × (1 − squared error). This evaluates the estimate against known odds, rather than awarding skill based on a lucky sampled outcome.
What chips and points mean
Virtual chips represent simulated game outcomes. Skill rating measures scored decisions. Learning points are a separate balance earned only through eligible learning activity. Chips and rating cannot be converted into learning points or pricing offers.
Ranked play
A free account is required for scored public competition. Ranked actions and outcomes are validated by the server; practice is unranked. Leaderboards compare the published rule version and disclose qualifying participation requirements.
Related
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