Ranged Estimates (video)

Learn how to capture uncertainty in your project plans from the start using ranged estimates and watch the schedule update automatically as scope changes.

Estimating is your best guess for how long it takes to get your work done.

And it’s hard. There are a lot of variables to consider, it’s difficult anticipate what will happen to your schedule.

You need to capture uncertainty and manage it in your project plans.

The way to do it is by using a range to estimate work.

A best case – worst case estimate is your honest assessment of how much effort it’ll take to finish a task assignment.

If things go well, work will be done in a shorter amount of time. If not, it’ll take longer.

And most likely – it’ll land somewhere in between, but you need help predicting that.

LiquidPlanner uses the range to statistically calculate and forecast your project schedule.

Here’s what you need to keep in mind while estimating:

(ON SCREEN) Effort, not duration

The estimate is about your effort, not duration.

(ON SCREEN) Wider range = more uncertainty

Use a wider range any time you’re unsure about the scope of work or when it’s something you haven’t tried before. If you’re having trouble break a task down into multiple assignments and apply wider ranges to the parts that have more uncertainty.

(ON SCREEN) Update estimates as you go along

Update estimates when you have a better idea about what to expect.

Ranged estimates provide a natural way to account for the uncertainty and incorporate it into your plans for a more realistic schedule.

Let’s look at it in Project View.

In order for a task to schedule, it needs to be assigned and estimated. Like this one. Open the edit panel, assign it to a member or resource and estimate.

Remember to enter it as a best case, worst case range.

The scheduling engine calculates dates and creates the schedule bar as soon as you save the estimate.

It uses the range to calculate a landing zone for your work,

Expected Start is when you’re most likely to begin

Expected Finish is the date you’re working toward, this is the likely finish date

Latest Finish is how long it could take if worst case estimates come into play

Uncertainty is the white space between expected finish and latest finish. More white space means more uncertainty. If you’re concerned about how far apart these dates are, then it’s time to dig in and figure it out.