Using Ranged Values When Expressing Estimated Outcomes

The most explicit way of accommodating uncertainty is as much of an issue of style as of mathematics. Whenever you're asked to provide an estimate for anything, project management best practice dictates that you should express the estimate as a range of possible outcomes, rather than one specific number.

Try it. The next time you prepare a cost estimate, for example, tell your management this: "I can state to a 95% degree of certainty that the project will cost between $100,000 and $125,000."

Then step back and wait for the reaction. It probably won't be favorable. Unfortunately, it should be, because you've provided some very valuable information. And you've done the best you could, given the uncertainty you're facing. The problem is that people are usually looking for a specific figure. Unfortunately, you cannot—in good conscience—provide a specific figure. Do you remember that uncertainty is defined as an absence of information, knowledge, or understanding regarding the outcome of an action, decision, or event? Well, you're likely to have truckloads of uncertainty at the outset of a project. You should publicize this uncertainty, not mask it behind a single figure—namely, that "best guess" you were asked to provide.

Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

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