Project Planning
Resource planning
In our case study it is clear that Steve and Susan have resource problems.
Getting a handle on all of the tasks that have to be done is a great start, but
it's not enough to know the tasks and the order they come in. Before you
can put the final schedule together, you need to know who is going to each
job, and the things they need available to them in order to do it!
We've got so much to do! Invitations, catering, music... and I've got no idea
who's going to do it all. I'm totally overwhelmed.
From this statement it is clear that Susan is worried about human resources.
In comparison, Steve realizes that not all resources are people!
And it's not just people! We need food, flowers, a cake, a sound system, and
a venue! How do we get a handle on this?
Resources are people, equipment, locations, or anything else that you need
in order to do all of the activities that you planned for. Every activity in
your activity list needs to have resources assigned to it. Before you can
assign resources to your project, you need to know which ones you're
authorized to use; that's called resource availability. Resource availability
includes information about what resources you can use on your project and
when they're available to you. Don't forget that some resources like
consultants or training rooms have to be scheduled in advance, and they
might only be available at certain times. You'll need to know this before
you can finish planning your project. If you are starting to plan in January, a
June wedding is harder to plan than one in December, because the wedding
halls are all booked up in advance. That is clearly a resource constraint.
You'll also need the activity list that you created earlier, and you'll need to
know about how your organization typically handles resources. Once
you've got a handle on these things, you're set for resource estimation.
Estimating the resources
The goal of activity resource estimating is to assign resources to each
activity in the activity list. There are five tools and techniques for the
activity resource estimating process. Some of them have technical sounding
names, but they're all actually pretty sensible when you think about it. They
should make sense to you when you think about what you have to do when
you have to figure out what resources your project needs.
- Expert judgment means bringing in experts who have done this sort
of work before and getting their opinions on what resources are needed
(Figure 15).
- Alternative analysis means considering several different options for
how you assign resources. This includes varying the number of
resources as well as the kind of resources you use. Many times, there's
more than one way to accomplish an activity and alternative analysis
helps decide among the possibilities.
- Published estimating data is something that project managers in a lot
of industries use to help them figure out how many resources they
need. They rely on articles, books, journals, and periodicals that
collect, analyze, and publish data from other people's projects.
- Project management software such as Microsoft project will often have features designed to help project managers estimate resource needs and constraints and find the best combination of assignments for the project.
- Bottom-up estimating means breaking down complex activities into pieces and working out the resource assignments for each piece. It is a process of estimating these individual activities or costs and then adding these up together to come up with a total estimate. Here you estimate every scheduled activity individually and then roll up that estimate; or add them all together, to come up with a total. Bottom-up estimating is a very accurate means of estimating, provided the estimates at the schedule activity level are accurate. However, it takes a considerable amount of time to perform bottom-up estimating because every activity must be accessed and estimated accurately to be included in the bottom-up calculation. The smaller and more detailed the activity, the greater the accuracy and cost of this technique.
Figure 15: "I know nothing about the subject but I am happy to give you my expert opinion".
In each of the following scenarios for planning Steve and Susan's wedding
determine which of the five activity resource estimation tools and
techniques is being used.
Exercise 2:
Problem:
Sally has to figure out what to do for the music at Steve and Susan's
wedding. She considers using a DJ, a rock band, or a string quartet.
Exercise 3:
The latest issue of Wedding Planner's Journal has an article on
working with caterers. It includes a table that shows how many waiters
work with varied guest-list sizes.
Exercise 4:
There's a national wedding consultant who specializes in Caribbean
themed weddings. Sally gets in touch with her to ask about menu
options.
Exercise 5:
Sally downloads and fills out a specialized spreadsheet that a project manager developed to help with wedding planning.
Exercise 6:
There's so much work that has to be done to set up the reception hall
that Sally has to break it down into five different activities in order to
assign jobs.
Exercise 7:
Sally asks Steve and Susan to visit several different caterers and
sample various potential items for the menu.
Exercise 8:
Sally calls up her friend who knows specifics of the various venues in their area for advice on which one would work best
Estimating activity durations
Once you're done with activity resource estimating, you've got everything
you need to figure out how long each activity will take. That's done in a
process called activity duration estimating. This is where you look at each
activity in the activity list, consider the scope and the resources and
estimate how long it will take to perform.
Estimating the duration of an activity means starting with the information
you have about that activity and the resources that are assigned to it, and
then working with the project team to come up with an estimate. Most of
the time you'll start with a rough estimate and then refine it to make it more
accurate. You'll use these five tools and techniques to create the most
accurate estimates:
- Expert judgment will come from your project team members who are
familiar with the work that has to be done. If you don't get their
opinion, then there's a huge risk that your estimates will be wrong.
- Analogous estimating is when you look at activities from previous
projects that were similar to this one and look at how long it took to do
similar work before. But this only works if the activities and the
project team are similar!
- Parametric estimating means plugging data about your project into a
formula, spreadsheet, database, or computer program that comes up
with an estimate. The software or formula that you use for parametric
estimating is built on a database of actual durations from past projects.
- Three-point estimates are when you come up with three numbers: a
realistic estimate that's most likely to occur, an optimistic one that
represents the best-case scenario, and a pessimistic one that represents
the worst-case scenario. The final estimate is the average.
- Reserve analysis means adding extra time to the schedule (called a contingency reserve or a buffer) to account for extra risk.
In each of the following scenarios for planning Steve and Susan's wedding
determine which of the five activity duration estimation tools and
techniques is being used.
Exercise:
Problem:
Sally comes up with three estimates (one where everything goes
wrong, one where some things go wrong, and one where nothing goes
wrong) for printing invitations, and average them together to come up
with a final number.
Exercise:
Problem:
Sally comes up with three estimates (one where everything goes
wrong, one where some things go wrong, and one where nothing goes
wrong) for printing invitations, and averages them together to come up
with a final number.
Exercise 9:
There are two different catering companies at the wedding. Sally asks
the head chef at each of them to give her an estimate of how long it
will take each of them to do the job.
Exercise 10
There's a spreadsheet Sally always uses to figure out how long it takes
guest to RSVP. She enters the number of guests and their zip codes,
and it calculates estimates for her.
Exercise 11:
Sally's done four weddings that are very similar to Steve and Susan's, and in all four of them it took exactly the same amount of time for the caterers to set up the reception hall
You've got a list of activities, you know what resources are needed to
actually do each activity, and you've got your estimation tools and
techniques, now you have enough information to create the estimate! The
activity duration estimates are an estimate of how long each activity in the
activity list will take. This is a quantitative measure usually expressed in
hours, weeks, days, or months. Any work period is fine, and you'Il use
different work periods for different jobs. A small job (like booking a DJ)
may just take a few hours; a bigger job (like catering-including deciding on
a menu, ordering ingredients, cook food and serving guests on the big day)
could take days.
Another thing to keep in mind when estimating the duration of the
activities, is determining the effort involved. Duration is the amount of the
time that an activity takes, while effort if the total number of person-hours
that are expended. If it takes two people six hours to carve the ice sculpture
for the centerpiece of a wedding, the duration is six hours. But if two people
worked on it for the whole time, it took twelve person-hours of effort to
create!
You'll also learn more about the specific activities while you're estimating
them. That's something that always happens. You have to really think
through all of the aspects of a task in order to estimate it. As you learn more
about the specific activities remember to update the activity attributes.
If we go back to our case study of the wedding we can see that while Sally
has got a handle on how long things are going to take, that's not enough to
get the job done. She still has some work to do before she's got the whole
project under control. Steve and Susan know where they want to get
married, and they've got the place booked now, but what about the caterer?
They have no idea who's going to be providing food. And what about the
band they want? Will the timing with their schedule work out?
If the caterers come too early, the food will sit around under heat lamps!
But, if they come too late, then the band won't have time to play. I just
don't see how we'll ever work this out!
It's not easy to plan for a lot of resources when they have tight time
restrictions and overlapping constraints. How do you figure out a schedule
that makes everything fit together? You're never going to have the complete
resource picture until your done building the schedule. And the same goes
for your activity list and duration estimates too! It's only when you lay out
the schedule that you'll figure out that some of your activities and durations
didn't quite work.
Project schedule
The project schedule should be approved and signed off by stakeholders
and functional managers. This assures they have read the schedule,
understand the dates and resource commitments, and will likely cooperate.
You'll also need to obtain confirmation that will be available as outlined in
the schedule. The schedule cannot be finalized until you receive approval
and commitment for the resource assignments outlined in it.
Once the schedule is approved, it will become your baseline for the
remainder of the project. Project progress and task completion will be
monitored and tracked against the project schedule to determine if the
project is on course as planned.
The schedule can be displayed in a variety of ways, some of which are
variations of what you have already seen. Project schedule network
diagrams will work as schedule diagrams when you add the start and finish
dates to each activity. These diagrams usually show the activity
dependencies and critical path.
The critical path method is an important tool for keeping your projects on
track. Every network diagram has something that is called the critical path.
It's the string of activities that, if you add up all of the durations, is longer
than any other path through the network. It usually starts with the first
activity in the network and usually ends with the last one.
Steve: Aunt Jane is a vegetarian. That won't be a problem, right?
Susan: Well, let's see. What menu did we give the caterers?
Steve: We didn't give it to them yet because we won't have the final menu until everyone RSVPs and lets us know which entrée they want.
Susan: But they can't RSVP because we haven't sent out the invitations! What's holding that up?
Steve: We're still waiting to get them back from the printer. We can't send them out if we don't have them yet!
Susan: Oh no! I still have to tell the printer what to print on the invitations and what paper to use.
Steve: But you were waiting on that until we finished the guest list.
Steve thought Aunt Jane being a vegetarian was just a little problem. But it
turns out to be a lot bigger than either Steve or Susan realized at first!
How'd a question about one guest's meal lead to such a huge mess?
The reason that the critical path is critical is that every single activity on the
path must finish on time in order for the project to come in on time. A delay
in any one of the critical path activities will cause the entire project to be
delayed (Figure 16).
Figure 16: An example of problems that can be caused within the critical path.
Knowing where your critical path is can give you a lot of freedom. If you
know an activity is not on the critical path, then you know a delay in that
activity may not necessarily delay the project. This can really help you
handle emergency situations. Even better, it means that if you need to bring
your project in earlier than was originally planned, you know that by adding
resources to the critical path will be much more effective than adding them
elsewhere.
It's easy to find the critical path in any project! Of course, on a large project
with dozens or hundreds of tasks, you'll probably use software like
Microsoft Project to find the critical path for you. But when it does, it's
following the same exact steps that are followed here.
Step 1. Start with a network diagram
Step 2. Find all the paths in the diagram. A path is any string of activities that goes from the start of the project to the end.
Start > Activity "A" > Activity "B" > Finish
Start > Activity "A" > Activity "C" > Finish
Start > Activity "D" > Activity "E" > Finish
Step 3. Find the duration of each path by adding up the durations of each of the activities on the path.
Start > Activity "A" > Activity "B" > Finish = 4 + 7 = 11
Start > Activity "A" > Activity "C" > Finish = 4 + 2 = 6
Start > Activity "D" > Activity "E" > Finish = 3 + 5 = 8
Step 4. The first path has a duration of 11, which is longer than the other paths, so it's the critical path.
The schedule can also be displayed using a Gantt chart (Figure 17). Gantt charts are easy to read and commonly used to display schedule activities. Depending on the software you use to display the Gantt chart, it might also show activity sequences, activity start and end dates, resource assignments, activity dependencies, and the critical path. Gantt charts are also known as bar charts.
Figure 17: An example of a Gantt chart.