Draw cards randomly from a deck and observe how the running variance (average of squared differences) converges to the theoretical variance. Toggle cards to change the distribution.
Variance Convergence
Running variance (green) converges to theoretical variance (blue)
Current Card
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Card Deck Selection
Toggle Cards
Click cards to include/exclude them from the deck.
Understanding Variance
Variance Formula
Measures the spread of a distribution:
Var(X) = E[(X - E[X])²]
Average of squared differences from the expected value.
Convergence
As you draw more cards, the running variance (green line) converges to the theoretical variance (blue dashed line).