π
Σ

🧙‍♂️ Bayes Theorem Learning Lab 🧮

Transform static formulas into intuitive understanding

Parameter Controls

Evidence P(B): 5.94%
(Auto-calculated with 5% false positive rate)

Bayes' Formula

P(A|B) =
P(B|A)
0.950
×
P(A)
0.010
P(B)
0.059
Posterior Probability
15.99%
Probability of A given evidence B

2×2 Contingency Table

B True
B False
A True
0.9%
0.1%
A False
5.0%
94.1%

Population of 100 People

Has A
Has B
Has A given B

💡 Insights

  • • Base rate: 1.0% of population has condition A
  • • Test accuracy: 95.0% sensitivity
  • • If you test positive, there's a 16.0% chance you have A
  • ⚠️ Even with a positive test, A is more likely absent due to low base rate!