Spreadsheet Models for Managers


Getting Access to Spreadsheet Models for Managers


If Spreadsheet Models for Managersyou use Excel to model businesses, business processes, or business transactions, this course will change your life. You’ll learn how to create tools for yourself that will amaze even you. Unrestricted use of this material is available in two ways.

As a stand-alone Web site
It resides on your computer, and you can use it anywhere. No need for Internet access.
At this Web site
If you have access to the Internet whenever you want to view this material, you can purchase on-line access. Unlimited usage. I’m constantly making improvements and you’ll get them as soon as they’re available.

To Order On Line

Order "Spreadsheet Models for Managers, on-line edition, one month" by credit card, for USD 69.95 each, using our secure server, and receive download instructions by return email.
Order "Spreadsheet Models for Managers, on-line edition, three months" by credit card, for USD 199.00 each, using our secure server, and receive download instructions by return email.
Order "Spreadsheet Models for Managers, downloadable hyperbook edition" by credit card, for USD 199.00 each, using our secure server, and receive download instructions by return email.

To Order by Mail

Make your check payable to Chaco Canyon Consulting, for the amount indicated:
  • For the download: USD 199.00
  • For access online for three months: USD 199.00
  • For access online for one month: USD 69.95
And send it to:
Chaco Canyon Consulting
700 Huron Avenue, Suite 19C
Cambridge, MA 02138

To use the course software you’ll need some other applications, which you very probably already have. By placing your order, you’re confirming that you have the software you need, as described on this site.

Spreadsheet Models for Managers

Example 12/11
Session Links
  • Fast food drive-thru
    • Customers arrive at a Poisson rate of 20/hr
    • Service times average 2.6 minutes, exponentially distributed
    • How long is the average waiting line?

      The length of the line
    • Excluding empty lines, what is the average line length?
      The length of the non-empty line

Consider the example of a simple fast-food drive-thru. And let’s assume that this drive-thru is one of the early ones — it isn’t staged (most of them are nowadays). If we’re given the arrival rate and the service rate, we can find the length of the average waiting line. And we can also find the length of the average waiting line excluding empty lines.

The first answer is just a straightforward application of the formula from the readings.

The second is obtained by dividing the first by the probability that there are more than one customer in the system. When there is only one customer, there is no line.

Last Modified: Wednesday, 27-Apr-2016 04:15:26 EDT

The Power of Simplifying Assumptions

Modeling service systems in general is extraordinarily complex, but as we’ve seen, if we make reasonable approximations, we can gain powerful tools that are very easy to apply. In the case of service systems, we assumed that the system was at equilibrium or close to it. Analogously, we can make simplifying assumptions for many other complex questions. Examples are process control, resource scheduling, resource allocation, cost allocation, vehicle routing, and many more.