Sunday 25 August 2019

Resource Optimization Techniques

now that we have our network diagram and from our activity list we are aware of which activities require what resources it's time to assign/allocate those resources throughout our project and identify any resource constraints we may have. up to now we haven't considered resources availability, we've just identified required resources but now that we have a network diagram of our project we can identify resource bottlenecks for example if two activities.

Our aim is to create a smooth resource distribution throughout the project as well as identify any resource over or under allocations.

Resource Smoothing
is a technique that is used to adjust activities within the constraint of the project duration to evenly distribute resources throughout the project it is done by establishing usage limits for each resource to ensure that resources are note over or under utilized. The float of non critical items is used to reschedule activities to smooth out the use of resources.

Resource Leveling 
is used when resource smoothing is not sufficient to distribute resources without elongating the project. It's a technique that involves adjusting the start and finish dates with the intent of balancing demand with availability of resources. leveling will defer activities until required resources are available, this may very well elongate the project. That is leveling doesn't factor in activity float.

in the event that resource smoothing is not enough and we need to utilize resource leveling odds are that we have to either adjust our project deliver date or we need to allocate more resources to the project, either way we must return to the sponsor and align either we add resources or increase the schedule. if we add resources we must ensure that these are captured in the resources activity list

Tuesday 20 August 2019

Network Diagramming

Project scheduling often leverages a network diagram, this is the case because network diagrams provide two major benefits

  • displays the critical path: activities that must be done end to end
  • reveals flexibility: places we can optimize resources to increase delivery

this visual representation of all the activities that must be done in a particular order is invaluable to understand a project

insert diagram

Critical Path method
this method is used to map the shortest path possible to project completion, it also reveals the tasks that if delayed will ultimately delay the project delivery. The critical path is the longest path from project start to finish whereas the non-critical paths can be adjusted in duration within reason and not affect the project delivery date.

With the network diagram complete and our critical path identified we can look at our alternative paths and identify their slack or float value, that is the amount of time from the earliest start date for each activity that can be deferred or extended without pushing the projects delivery date.

To Identify our critical path

Forward pass analysis
is the process of moving through each path identifying the earliest start and end date for each activity.

  • Earliest start date (ES) is the earliest date that an activity can begin with respect to it's predecessor relationships
  • Earliest finish date (EF) is the earliest date that an activity can finish, (ES + duration)

insert diagram

float: is between paths is the difference between the duration of the critical path and all alternative paths, each alternative path has it's own float value, that value is how many days that path can be delayed without delaying the project

Backward pass analysis
The backward pass analysis is the process of moving from the end of our project back to the beginning to determine the latest start date and the latest finish date for each activity

  • Latest start date (LS) is the latest date an activity can start without delaying the project delivery. (LF - Duration)
  • Latest finish date (LF) is the latest date that an activity can finish without delaying the project delivery.
Activities who's ES & EF values are the same as their LS & LF values are on the critical path.
the difference between an activities LS and ES is the float

Thursday 15 August 2019

Reconciling Estimates

As we've mentioned before, when the developing the project charter it is common to use a top-down estimating approach, however once the charter is signed off at the end of the project initiation phase it's time to start the project planning phase. In the planning phase when building the work breakdown structure it is time to implement the more accurate estimation approach of bottom-up.

In the Planning phase when a bottom up estimation is completed it is common for the two estimations to be different, this is of course the result of the bottom up approach being more labor intensive, difficult and accurate than the top down approach. More often than not the bottom-up approach is generally higher than the top-down, this is usually because of political reasons or optimistic estimations or just during the charter the whole scope just wasn't evident.

When the bottom-up estimation is higher than the top-down estimation
  • Ask the project sponsor for more budget to cover the difference in cost
  • Modify the scope by removing or scaling down requirements 
  • Negotiate with vendors to try to get better prices thus decreasing the budget required
  • Some combination of the above
If the bottom-up estimation is lower than the initial top-down estimation:
  • Settle with the project sponsor on the lower estimate
  • Add requirements to the scope to user up the extra budget
  • upgrade the current requirements
  • Some combination of the above
Once the project budget is finalized and it's allocation to activities, all agreed changes must be updated in the:
  • Project Charter
  • Requirements document
  • Scope Statement
  • Work Breakdown Structure
  • Activity List
All documents must reflect the agreed upon Resources, Scope, and Schedules and should always be kept in sync with the current agreement between the PM and Stakeholders.

When all reconciliation is complete and confirmed and the budget is aligned to the project scope, it's time to consider adding contingency funds based on the risks identified in the project. The contingency portion of the budget is additional money added to the budget to cover the cost of incurring potential risks that have been identified.

Saturday 10 August 2019

WBS: Budgeting

Once all activities are listed with their Duration & Effort estimates, the budget can be composed, the budget is the cost element of the triple constraint. Costs are allocated to the activity level, all costs including personnel, assets, subscriptions etc need to be allocated to get the most accurate estimate per activity as possible. even the estimate cost of contingencies is included in the estimating of activities.

since each activity is tied to it's precursor and successor; work packages are comprised of activities and deliverables are made up of work packages; with all this information we can track how much each deliverable will cost and when it will be delivered. The WBS and activity list are used to manage the triple constrained, the budget scope and schedule are managed together, the WBS and activity list documents are the corner stone of the project plan.

there are multiple ways to estimate to cost of activities

  • Bottom-up estimating: estimates are done from the bottom of the WBS, starting with estimating how much each activity will cost adding those values up to figure out the cost of a work package, etc up to the project
  • Top-down estimating: involves estimating how much a work package will cost, then dividing that estimate up among the activities, this can start at the project, deliverable or work package level.

there are pro's and con's of each

Top-down Estimating 
The advantage of top-down estimating is that it can be done fairly simply and quickly however it is not as accurate as bottom up estimating techniques, it is best used for the project selection or developing a project charter, some techniques are:

  • Pragmatic estimating: leverage historical data, for example a company can use data from previous projects similar in scope to estimate the cost of new projects. it leverages the cost per unit times how many units needed paradigm. 
  • Analogous estimating: leverages historical data, if a company completed a similar project, but twice the size you could argue that the new project will be similar in costs just divided by two.
  • Group Decision making: involves leveraging experts, each expert would create their own estimate for the project, deliverables, work packages and activities, then in an iterative fashion the experts discuss and narrow down to the best estimate.
  • Software estimating: leverages historical data with statistical analyses and various algorithms to help estimate as well as define odds of success vs failure. 

Bottom-up Estimating
The advantage of bottom-up estimating is that it's much more accurate however it's also far more difficult and involved, it requires granular analyses of each activity by experts then all costs for all activities are aggregated to come up with a project estimate.

it is recommended to use both a top-down and bottom-up estimation to get a more accurate understanding of the project cost. typically when project selection is done and the charter is written a top-down approach is used, then when in the planning phase it's normal to use the bottom-up approach to get a more accurate depiction on budget needed. if there's a discrepancy then it becomes a negotiation between the PM, sponsor and senior management of whether to decrease scope, increase budget or some combination of the two.

Monday 5 August 2019

WBS: Activities

Activity Planning
Activities make up work packages; activities are the line items inside of work packages that need to be completed to close a work package. some activities need to be completed before others, these are referred to as "predecessors". predecessor activities have to be completed before its "successor" activity. The "predecessor" to "successor" relationship is referred to as a "Finish to start" relationship.

By laying out all our activities with a predecessor successor relationship we can layout the timeline for our entire project. activities with no predecessor can be started on day one of the project, otherwise they need to be completed sequentially.

Predecessor relationships are only defined at the activity level and not the work package or deliverable levels.

Activity Resourcing
Once we've planned our activities we need to assign resources to them, these could be people, assets, commodities, services, supplies, materials, or money, basically anything that is required to complete the activity.

Activity Duration & Effort
After the resources are assigned to each activity it's time to estimate

  • Duration: The number of business days required for an activity; used to estimate schedule
  • Effort: The total number of hours required for an activity; used to determine the budget.

For example 3 employees could be working on a activity at the same time, so it would be 1 workday of duration but 24 hours of effort; or you could have 2 employees working 50% of an 8 hour work day on an activity that requires 12 hours of effort, two employees working half their time would have an 1.5 days of duration.

as always you're values are only as good as your estimates, ideally you would want the people who will be doing the work estimating or someone who has a good understanding for the activities and their complexity

Thursday 1 August 2019

Work Breakdown Structure

The Work Breakdown Structure is a hierarchical decomposition of the total scope of work to be carried out by the project team to accomplish the project objectives and create the required deliverables. The WBS is a key tool that can be used by PMs to define and manage scope, it is used to break down a project into smaller workable sections (work packages)

A WBS can be represented as a hierarchical tree diagram

Based on the complexity of the project the hierarchical tree could have more or less levels

Our WBS can also be represented as an outline

1         Project

1.1         Deliverable

1.1.1        Work Package         Activity A         Activity B         Activity C

1.1.2        Work Package         Activity D         Activity E         Activity F         Activity G

1.1.3        Work Package         Activity H         Activity I

1.2         Deliverable

1.2.1        Work Package         Activity J

1.2.2        Work Package         Activity K         Activity L

Both represent the same work breakdown structure.

When defining activities which represent the work that needs to be completed at a granular level within a WBS the order of each activity is the order it should be completed in. The rule of thumb for activities is that they should represent 1 to 2 weeks worth of effort for 1 resource, if they're out side of the 5 to 10 working day range then either they are too granular or too broad.