Calculadora do Teorema de Bayes

The Bayes' Theorem Calculator solves the problem of finding the probability of an event A given that event B has occurred, using prior information. The formula P(A|B) = P(B|A) * P(A) / P(B) updates the initial belief about A based on evidence B. For example, in medical diagnostics, it calculates the actual chance of a disease after a positive test, considering test accuracy and disease prevalence.

It works simply: enter the probabilities P(A) (prior probability of A), P(B|A) (likelihood), and P(B) (marginal probability of B). The calculator returns P(A|B), the posterior probability. P(B) can be computed as P(B|A)*P(A) + P(B|not A)*P(not A), but here you provide the direct value. This helps avoid manual errors and speeds up statistical analysis.

Use this tool in situations like: evaluating the effectiveness of a medical test, predicting the probability of a customer defaulting based on history, or in spam filtering systems. It is essential in areas such as artificial intelligence, data science, and epidemiology, where evidence-based decisions are critical.

Caution: ensure the probabilities entered are accurate and represent the same population. The marginal probability P(B) must include all ways B can occur. Remember, Bayes' theorem does not create certainty; it only quantifies uncertainty based on available data.