PSY 330 Human Factors
5/1/00
Day 2-20
Effects of System Complexity on Reliability
uIn general reliability goes down as number of components goes up (i.e. as complexity goes up).
uComponents in a Series
lIn a series if any single component fails the whole system fails - the four tires on the car.
lRs = R1 * R2 * ... * Rn
lExamples: All components have reliability of 0.90.
ln = 1 | Rs = = .90
ln = 2 | Rs = .9*.9 = .81
ln = 3 | Rs = .9*.9*.9 = .73
ln = 10 | Rs = .910 = .35