XXooptRobotics

Posterior probability of an obstacle from a noisy proximity sensor

easynumerical

General

A mobile robot uses a binary proximity sensor to decide whether a grid cell ahead is occupied by an obstacle. From a map prior, the probability that any given cell contains an obstacle is P(O)=0.05P(O) = 0.05. The sensor has a true-positive rate (sensitivity) of P(DO)=0.95P(D \mid O) = 0.95 and a false-positive rate of P(D¬O)=0.10P(D \mid \lnot O) = 0.10, where DD denotes 'sensor reports detection'. Given a single detection, what is the posterior probability P(OD)P(O \mid D) that the cell is actually occupied? Give your answer as a percentage.

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