Reveal evidence card by card, watch your belief shift toward the hidden source, and resist the urge to call it too soon.
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How to play
A hidden source is one of several candidate distributions. Each card you draw is a piece of evidence; your belief bars update according to Bayes' rule. You score for guessing right with as few draws as you can responsibly take, but stopping too early on a lucky streak is punished.
Draw a card to reveal evidence and update the posterior over every hypothesis.
Watch the confidence-interval width shrink as samples accumulate.
Commit to a hypothesis once you're confident enough.
Your score rewards a correct call balanced against how many cards you sampled and the round's target.
Controls
Desktop: click Draw (or press Space / Enter) to reveal a card; click a hypothesis bar to commit; pick Daily/Practice and easy/medium/hard.
Phone & tablet: tap to draw and tap a hypothesis to commit, fully touch-friendly.
Tips & strategy
Don't anchor on the first card or two, a single draw barely moves a well-formed prior.
Use the confidence-interval width as your stop signal rather than the leading bar alone.
Higher difficulties make the candidate distributions more similar, so they demand more evidence.
What you'll learn
Posterior turns Bayesian inference into a press-your-luck decision, balancing accuracy against the cost of more evidence.
For parents & teachers: Bayesian inference as a decision.
About Posterior
Posterior turns Bayesian inference into a press-your-luck decision: balance accuracy against the cost of more evidence. It's an original, free browser game with daily and practice rounds across three difficulty levels.
A free, original browser game on PlayPendium. No download, no install.
