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Simulation. Inverse Functions. Actually, we’ve already done this with the normal distribution. 0.1. x. 3.0. 3.38. Inverse Normal. Actually, we’ve already done this with the normal distribution. -. m. X. =. x = m + s z = 3.0 + 0.3 x 1.282 = 3.3846. Z. s. f. (. x.
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Inverse Functions • Actually, we’ve already done this with the normal distribution.
0.1 x 3.0 3.38 Inverse Normal • Actually, we’ve already done this with the normal distribution. - m X = x = m + sz = 3.0 + 0.3 x 1.282 = 3.3846 Z s
f ( x ) e x F ( a ) Pr{ X a } a e x dx 0 1 e a Inverse Exponential Exponential Life 2.0 1.8 1.6 1.4 1.2 f(x) Density 1.0 0.8 0.6 0.4 0.2 0.0 0 0.5 1 1.5 2 2.5 3 e x a a Time to Fail 0
F(x) - l X e x Inverse Exponential F ( x ) = 1 -
F(x) - l a e F(a) x a Inverse Exponential F ( a ) = 1 -
F(x) F(a) x a Inverse Exponential Suppose we wish to find a such that the probability of a failure is limited to 0.1.
F(x) F(a) - l a e x a Inverse Exponential Suppose we wish to find a such that the probability of a failure is limited to 0.1. 0.1 = 1 -
F(x) F(a) - l a e x a Inverse Exponential Suppose we wish to find a such that the probability of a failure is limited to 0.1. 0.1 = 1 - ln(0.9) = -la
F(x) F(a) x - l a e a Inverse Exponential Suppose we wish to find a such that the probability of a failure is limited to 0.1. 0.1 = 1 - ln(0.9) = -la a = - ln(0.9)/l
Inverse Exponential Suppose a car battery is governed by an exponential distribution with l = 0.005. We wish to determine a warranty period such that the probability of a failure is limited to 0.1. a = - ln(0.9)/l = - (-2.3026)/0.005 = 21.07 hrs. F(x) F(a) x a
Model Customers arrive randomly in accordance with some arrival time distribution. One server services customers in order of arrival. The service time is random following some service time distribution.
- l » l A A e i i - m » m S S e i i M/M/1 Queue M/M/1 Queue assumes exponential interarrival times and exponential service times
- l » l A A e i i - m » m S S e i i M/M/1 Queue M/M/1 Queue assumes exponential interarrival times and exponential service times Exponential Review Expectations
2.032 1.951 1.349 .795 .539 .347 M/M/1 Queue 0.305 0.074 0.035 0.520 1.535 0.159
2.032 1.951 1.349 .795 .539 .347 0.305 0.074 0.035 0.520 1.535 0.159 M/M/1 Queue
M/M/1 Queue .347
M/M/1 Queue .347
M/M/1 Queue .539 .347 0.305
.795 M/M/1 Queue .539 0.652
.795 M/M/1 Queue .539 0.652 0.074
.795 M/M/1 Queue 0.726
.795 M/M/1 Queue
1.349 M/M/1 Queue .795 0.830 0.035
1.349 M/M/1 Queue 0.830
M/M/1 Queue 1.349
1.951 M/M/1 Queue 1.349 1.869 0.520
M/M/1 Queue 1.869 1.951
2.032 1.951 1.349 .795 .539 .347 0.305 0.074 0.035 0.520 1.535 0.159 M/M/1 Queue