Handbook of Civil Engineering Calculations

(singke) #1
Also,

^+^+^=1200 (d)


  1. Solve the system of equations
    The results are XAu = 411; Jf 5 M = 343; XCiU = 446. Thus, it is expected that there will ulti-
    mately be 411 units of model A, 343 units of model B, and 446 units of model C in use si-
    multaneously. Note that the values of XA>39 XE^ and A^ 3 in Table 36 are very close to the
    limiting values. Thus, the expected values approach their respective limits rapidly.
    Related Calculations: Many problems in engineering, economics, and other ar-
    eas lend themselves to solution as Markov processes. The computational techniques ap-
    plied in this calculation procedure and the preceding one are entirely general, and they
    may be applied to any problem where a Markov process exists.


VERIFICATION OF STEADY-STATE


CONDITIONS FOR A MARKOV PROCESS


Verify the accuracy of the results obtained in the preceding calculation procedure by de-
vising an alternative method of solution.


Calculation Procedure:


  1. Construct a recurring series of outcomes that conforms
    with the given process
    Assume that a Markov process has three possible outcomes, A, B, and C, and that the first
    35 outcomes were these:


B-A-A-B-B-A-C-C-C-C-B-A-A-A-C-C-A-A-A-C-C-B-A-B-A-B-C-C-C-C-A-B-C-B-B


This series consists of 12 A's, 10 B's, and 13 Cs. Also assume that this series of out-
comes will recur indefinitely. Thus, the last outcome in the series will be followed by B.
It will be demonstrated that this series is relevant to the preceding calculation procedure.



  1. Compute the transition probabilities as established
    by the recurring series
    Count the successors of the outcomes in this series, and then compute the relative fre-
    quencies of the various successions. Refer to Table 37 for the calculations. Since the giv-
    en series of outcomes will recur indefinitely, the relative frequencies in Table 37 equal the
    transition probabilities corresponding to the present Markov process. Thus, the probabil-
    ity that A will be followed by B is 0.3333, and the probability that C will be followed by
    A is 0.1538. Since these transition probabilities coincide with those in Table 35, it follows
    that the present recurring series provides a basis for investigating the Markov process in
    the preceding calculation procedure.

  2. Compute the steady-state probabilities
    In the long run, the probability that a given outcome will occur is independent of some
    outcome in the distant past. In the recurring series, the relative frequencies of the out-
    comes are: outcome A, 12/35; outcome B, 10/35; outcome C, 13/35. These relative fre-
    quencies are the steady-state probabilities corresponding to the Markov process.

Free download pdf