Caroline
The following book has a reasonable amount of discussion on the
LogNormal distribution, in relation to simulation:
A.M. Law and W.D. Kelton (1991) "Simulation Modeling and
Analysis, 2nd edition" (McGraw-Hill International Editions)
Stewart Robinson
> I have written a DES model to simulate canal traffic passing through a
> flight of 6 locks. The system consists of two-way traffic(customers), with
> bi-directional locks (servers).
>
> In the model random numbers for the service procedure are generated using
> the inverse transformation method, to create 'a day in the life' of the lock
> system. I inititally modelled the lock procedure(service) using the Normal
> distribution, as it fits this distribution. However on occasions, due to
> high variance, there is a small chance that negative values can be produced.
> This is clearly not acceptable as it cannot take minus 0.5 minutes for a
> boat to enter a lock. In view of constraint I have now chosen Log-Normal
> because it is closely related to the Normal distribution, but is also is a
> positive and positively skewed distribution.
>
> Has anyone else used a Log-Normal distribution to describe length of service
> in a simulation model. Can anyone offer more information on this
> distribution as there appears to be very little written about it, compared
> to the Normal.
>
Dr Stewart Robinson
Lecturer in Operational Research and Systems
Warwick Business School
Warwick University
Coventry
CV4 7AL
UNITED KINGDOM
Tel: 44-(0)1203-522132
Fax: 44-(0)1203-524539
Email: [log in to unmask]
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