Going through the Risk Management planning process is fantastic for figuring out pessimistic, optimistic and most likely scenarios.
We did a little bit of work with this earlier as we estimated how much things will cost.
We can use the same technique to figure out how much time things take.
Even if you are using nothing but internal resources – think time = cost.
So for this, I’m assuming you’ve already broken down the activities of your project.
Now that you’ve got your activity list and have a good idea of what needs to happen when – it’s time to take those activities and figure out how long each activity is going to take.
Most of us do this on the fly. We can be a bit more mindful about it. Especially since we often don’t account for the things that can go wrong (like the production laptop dying – which should be on your Risk Register).
Again, I like Three-Point Estimating for this.
We used this for cost before. We can also use this for time.
Step 1: Create 3 estimates
– Most likely (tM) – The time the activity will take based on realistic
effort assessment for the required work. Before learning this technique, I tended to use most likely(based on my personal development speed) + 3 days for time estimates for development activities.
– Optimistic (tO) – The time the activity will take based on best-case scenario. Opportunities should be in your risk register. Things such as getting the star developer on the project or a template appears that you didn’t know about or finding a design model from elsewhere that cuts your research time. Accounting for optimistic scenarios gives you ammunition for when the project champions and executives invariably move your project deadline forward.
– Pessimistic (tP) – The time the activity will take based on everything going horrifically wrong. The developer quits and you need to onboard a new person to the project who has never used Captivate before. The developer’s laptop dies. Your project champion leaves the organization and no one is willing to make decisions. All of it should be in the Risk Register. And you need to try to have a realistic view of how likely that scenario will happen. For disasterizers like myself, that can be hard. Hence the Risk Register probability / impact matrix exercise.
Step 2: Plug resulting numbers into formulas
There are two ways to calculate expected time for each activity.
Depending on your organization, they may want to see one or both calculations.
tE = Expected time
– Triangular Distribution. The average of the most likely, optimistic and pessimistic time scenarios.
tE = (tM + tO + tP) / 3
– Beta Distribution. This uses the PERT (Program Evaluation and
Review Technique) technique to get a weighted estimate between
optimistic, pessimistic and most likely scenarios. The assumption is
that the most likely scenario is 4x more likely to happen than either
the optimistic or pessimistic scenarios.
tE = (4tM + tO +tP) / 6
This information will allow you to build the first draft of the project schedule.
- An optimistic scenario – where everything goes right and then some.
- A likely scenario – the “realistic” time frame
- A pessimistic scenario – where the project gets finished, but everything goes wrong
My first draft of a project schedule for the types of projects I do (instructional design and development projects, simple learning applications / solutions implementations) assumes that everything follows each other and nothing happens in parallel.
We know life doesn’t work like that.