Question

A sensor is used to monitor the performance of a nuclear reactor. The sensor accurately reflects the state of the actor with probability of .97. But with a probability of .02, it gives false alarm, ( by reporting excessive radiation even though the reactor is performing normally, and with a probability of .01, it misses excessive radiation ( by failing to report excessive radiation even though the reactor is performing abnormally). a) what is the probability that a sensor will give an incorrect report, either a false alarmor a miss? b) To reduce costly shut downs caused by false alarms, management introduces a second completely independent sensor, and the reactor is shut down only when both sensors report excessive radiation. (According to this perspective, solitary reports of excessive radiation should be viewed as false alarms and ignored, since both sensors provide accurate information much of the same time. ) What is the new probability that the reactor will shut down because of simultaneous false alarms by both the first and second sensors? c) Being more concerned about failures to detect radiation, someone who lives near the nuclear reactor proposes an entirely different strategy: shut down the reactor when ever either sensor reports excessive radiation. (According to this point of view, even a solitary report of excessive radiation should trigger a shutdown, since a failure to detect excessive radiation is potentially catastrophic. ) If this policy were adopted, what is the new probability that excessive radiation will be missed simultaneously by both the first and second sensors?

Answer 1