Waiting Line Models:

Generally these tools are utilized in the industries for capacity planning. The waiting lines tend to be developed in front of the work centre, such as railway reservation counters, bank counter, machine center or a central computer. The reason is quite simple because the arrival time of jobs or customers varies and processing time can vary from one customer to another. Waiting line model uses the probability distributions to provide estimates of average customer delay time, average length of waiting lines, and utilizations of the work center. Managers may use this information to choose the most effective capacity, balancing customer service and the cost of adding capacity.

The waiting lines increment provides a fuller treatment of waiting lines. It introduces formulas for the estimation of important characteristics of a waiting line, such as average customer waiting time and average facility utilization, for different facility designs. For instance, a facility may be designed to have multiple lines at each operation and to route customers through one or multiple operations. Given the estimating capabilities of these formulas and cost estimates for waiting and idle time, managers may select cost effective designs and capacity levels that also provide the wanted level of customer service.