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Queuing Theory Articles

Queueing Theory is is the mathematical study of waiting lines, or queues. Queueing Theory enables mathematical analysis of several related processes, including the following:

On average, how many will arrive at the (back of the line) queue?
On average, how long will one wait in the queue?
On average, how long will one wait until being served at the front of the queue?

Below are several posts on Queueing Theory. I’ll be adding to this page periodically — applications, best practices, and general items:

Social Security Office: A Lesson on Queueing

by Pete Abilla on September 8, 2011

Due to an overly-busy life, I forgot to apply for a social security card for my youngest daughter, the baby. She’s 1.5 years and so I thought I probably should just grin and bear it and head over to our local social security office. So, I got the youngest 4 kids ready and we went [...]

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Cycle Time Reduction: Use Little’s Law

by Pete Abilla on August 10, 2011

little's law equation, reduce cycle time

We know that Little’s Law is the average number of customers in a system (over some interval) is equal to their average arrival rate, multiplied by their average time in the system. TH = throughput (arrival rate). This is the velocity or speed of production and is calculated by determining how many items are produced and dividing it by [...]

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Restaurant Wait Time and Customer Satisfaction

by Pete Abilla on July 19, 2011

I find Customer Satisfaction Surveys interesting. It gives us a sense of what is important to the firm and the type of information they are attempting on gathering gives us a clue as to what is important to the company. I was recently sent a survey from The Olive Garden, which is an Italian Restaurant [...]

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Queueing Psychology and Unexplained Delays

by Pete Abilla on May 19, 2011

annoying, flight delays, joe palca, queueing, psychology

Joe Palca, a National Public Radio (NPR) correspondent recently published a book entitled “Annoying: The Science of What Bugs Us”. In the book, Joe Palca and his co-author share a number of common things that are annoying and also some research on why those things are annoying to most of us. In his research, he [...]

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Japan Earthquake and Tsunami 2011, a Queue, Crowd Control, How You Can Help

by Pete Abilla on March 14, 2011

Most of you are aware of the terrible earthquake and tsunami that devastated Japan last week. What I want to highlight today, however, isn’t the disaster, but (1) the manner in which the Japanese people are responding to this terrible crisis and (2) share several ways we can help Japan during this time of adversity. [...]

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Little’s Law

by Pete Abilla on January 5, 2011

Given just a few properties of a queue, we can answer some questions about waiting times without knowing anything other than the average line length and the average customer arrival rate. For example, If a customer joins the line just after a customer begins to be served, then intuitively one would expect the newly arriving customer to [...]

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Queueing Theory Definition

by Pete Abilla on January 4, 2011

Below are common Queueing Theory definitions, glossary, and vocabulary. Knowing the concepts below will help you better understand these articles on Queues. Queue: A line (or buffer or inventory) feeding a number of servers Server: An operation fed by a queue. Arrival rate (λ): Mean number of arrivals per unit time (usually per hour or [...]

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Hajj: Eid ul-Adha and Queueing

by Pete Abilla on December 21, 2010

Eid ul-Adha is an Islamic holiday marking the last day of the Hajj, the annual pilgrimage to the holy city of Mecca. The Hajj is the largest organized movement of people in the world. One can only imagine the logistical nightmare for such a massive event – not to mention all the queueing properties that [...]

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