To accurately reflect your project's progress, project schedules must be continuously updated. This process enables stakeholders to evaluate impacts to the project as they occur. This provides better control over the project and reduces the impact of required changes.
A schedule update is any modification to the schedule information used to manage the project. Schedule updates are required when variances from plan are higher or lower than the previously approved limit. Schedule updates may or may not require adjustments to other aspects of the overall project management plan.
There is a special category of schedule updates called revisions. Revisions are changes to the scheduled start and finish dates in the approved project schedule. Typically, start and finish dates are only revised in response to scope changes. In cases where schedule slippage is severe enough to warrant revision, rebaselining may be required to provide realistic data for performance measurement.
Palmcom Computers is developing a new palm-sized computer. The company has planned for the product to be introduced at the Fall Buyer's Show. It has decided to strive for this date, to get the heads-up on the competition. Reaching this goal allows for very little flexibility. At the end of the second phase, the management team notices that the schedule is slipping, resulting in a variance much larger than the acceptable range. If this trend continues, the company will not have the originally planned two weeks for quality testing.
In this example, the company has two choices—alter the project scope, or change the project schedule. After careful examination, the team has decided to maintain the current completion date and adjust the allotted testing time to one week to give the team an extra week for production.
Ongoing monitoring and updating are essential components of project schedule control. Adjustments to the project start or finish date (revisions) require special attention. In the event a revision is necessary, the schedules need to be accurately revised for the key stakeholders to continue to have a valid means of measuring the project's overall progress.
Showing posts with label time. Show all posts
Showing posts with label time. Show all posts
Tuesday, March 18, 2008
Saturday, February 9, 2008
Components of Project Scheduling
Have you ever scheduled a job that required more time to complete than you had initially planned for? Did you know that calendars, leads, and lags can help you schedule the appropriate amount of time for a project activity?
Calendars
In much the same way you use an agenda to keep track of your day-to-day appointments, a project manager uses a calendar to ensure that a project is progressing according to plan.
Project managers use calendars to identify project workdays. Calendars can be altered so weekends and holidays are not included. The arrangement of normal working days, together with non-working days, such as holidays and vacations, and any overtime periods, are used to determine the project completion dates.
To create and use a project calendar, you need to know the range, units and start date.
Project calendars define global project working and non-working periods and affect all project resources. For example, work will only take place on weekdays.
Resource calendars affect specific resources or categories, like people, material or equipment. For example, scheduling around a team member's vacation.
Leads and lags
What would you do if your project was delayed by three weeks, while you were waiting for a necessary piece of equipment to arrive?
Dependencies within a project may require detailed specifications to accurately define the relationships. These specifications are in the form of leads and lags, which are important aspects of the schedule development process.
Remember, if your project needs to reflect an assumed delay you may need to implement a lag at the anticipated interval in the schedule. On the other hand, if your project has imposed constraints such as time or future restriction on resources, your schedule may need to include a lead.
Understanding why you must include these components in your resource and project calendars will increase the odds of keeping your project on track, ensuring a successful completion.
Calendars
In much the same way you use an agenda to keep track of your day-to-day appointments, a project manager uses a calendar to ensure that a project is progressing according to plan.
Project managers use calendars to identify project workdays. Calendars can be altered so weekends and holidays are not included. The arrangement of normal working days, together with non-working days, such as holidays and vacations, and any overtime periods, are used to determine the project completion dates.
To create and use a project calendar, you need to know the range, units and start date.
- The calendar range is the calendar's span from the start date, up to and including the last date work is performed.
- Calendar units can be in hours, days, weeks, shifts, and minutes. They are the smallest unit of time used for scheduling the project.
- The calendar start date is the first calendar unit of the working calendar.
Project calendars define global project working and non-working periods and affect all project resources. For example, work will only take place on weekdays.
Resource calendars affect specific resources or categories, like people, material or equipment. For example, scheduling around a team member's vacation.
Leads and lags
What would you do if your project was delayed by three weeks, while you were waiting for a necessary piece of equipment to arrive?
Dependencies within a project may require detailed specifications to accurately define the relationships. These specifications are in the form of leads and lags, which are important aspects of the schedule development process.
- A lead is a modification of a logical relationship allowing for the acceleration of the successor task. For example, in a finish-to-start dependency with a five-day lead, the successor activity can start five days before the predecessor has finished.
- A lag is a modification of a logical relationship which directs a delay in the successor task. For example, in a finish-to-start dependency with a five-day lag, the successor activity cannot start until five days after the predecessor has finished.
Remember, if your project needs to reflect an assumed delay you may need to implement a lag at the anticipated interval in the schedule. On the other hand, if your project has imposed constraints such as time or future restriction on resources, your schedule may need to include a lead.
Understanding why you must include these components in your resource and project calendars will increase the odds of keeping your project on track, ensuring a successful completion.
Friday, January 18, 2008
Project Activity Duration Reserve Time
You've probably heard of the Army Reserves. The Reserves are made up of citizens who are trained as soldiers and who can be called upon in situations that demand extra resources.
Similarly, reserve time is added to project activity durations to provide the extra time that may be needed based on identified risks. Risks can affect the project schedule and cause delays. Reserve time helps offset such delays.
Reserve time should be documented along with other data and assumptions relating to the project. Reserve time, like other assumptions, is contingent on project results and subject to change as the project progresses. Two methods you can use to determine reserve time are discussed below.
1. As a percentage of activity duration
Reserve time is normally calculated as a percentage of the estimated activity duration. Using this method, reserve time can be calculated by simply adding an extra percentage to each activity duration estimate.
Reserve time can be reduced or eliminated as specific project information becomes available. Its use is at the discretion of the project team and is normally guided by expert judgment or historical information.
Consider this example. You are managing a road construction project and you have estimated that it will take you 50 days to build an overpass. After consulting with one of your lead engineers, an expert on highway construction, you decide to add an additional 20 percent to the duration estimate as reserve time.
To calculate the reserve time as a percentage of the estimated activity duration, you simply multiply your duration of 50 days by 20 percent. The reserve time for this activity is 10 days.
2. As a fixed number of work periods
Another approach to creating reserve time involves simply tacking on an additional fixed number of work periods to the current estimates for each activity. Work periods are often measured in days, but may vary by project.
Let's say you're managing a similar road construction project and you have estimated once again that it will take you 50 days to build an overpass. This time, though, after reviewing historical information on similar projects, you decide to calculate the reserve time by adding five additional work periods, or days, to your estimate.
If you take into account your reserve time of five work periods, your adjusted activity duration estimate for building the overpass would be 55 days.
Whether you decide to determine reserve time as a percentage of the estimated activity duration or as a fixed number of work periods, make sure you consult with a team member who is familiar with the given activity. This will help ensure that the reserve time you decide upon is as accurate as possible.
When performing activity duration estimates for your project, remember to allow for reserve time to accommodate circumstances that could interrupt or delay the progress of your project activities.
Similarly, reserve time is added to project activity durations to provide the extra time that may be needed based on identified risks. Risks can affect the project schedule and cause delays. Reserve time helps offset such delays.
Reserve time should be documented along with other data and assumptions relating to the project. Reserve time, like other assumptions, is contingent on project results and subject to change as the project progresses. Two methods you can use to determine reserve time are discussed below.
1. As a percentage of activity duration
Reserve time is normally calculated as a percentage of the estimated activity duration. Using this method, reserve time can be calculated by simply adding an extra percentage to each activity duration estimate.
Reserve time can be reduced or eliminated as specific project information becomes available. Its use is at the discretion of the project team and is normally guided by expert judgment or historical information.
Consider this example. You are managing a road construction project and you have estimated that it will take you 50 days to build an overpass. After consulting with one of your lead engineers, an expert on highway construction, you decide to add an additional 20 percent to the duration estimate as reserve time.
To calculate the reserve time as a percentage of the estimated activity duration, you simply multiply your duration of 50 days by 20 percent. The reserve time for this activity is 10 days.
2. As a fixed number of work periods
Another approach to creating reserve time involves simply tacking on an additional fixed number of work periods to the current estimates for each activity. Work periods are often measured in days, but may vary by project.
Let's say you're managing a similar road construction project and you have estimated once again that it will take you 50 days to build an overpass. This time, though, after reviewing historical information on similar projects, you decide to calculate the reserve time by adding five additional work periods, or days, to your estimate.
If you take into account your reserve time of five work periods, your adjusted activity duration estimate for building the overpass would be 55 days.
Whether you decide to determine reserve time as a percentage of the estimated activity duration or as a fixed number of work periods, make sure you consult with a team member who is familiar with the given activity. This will help ensure that the reserve time you decide upon is as accurate as possible.
When performing activity duration estimates for your project, remember to allow for reserve time to accommodate circumstances that could interrupt or delay the progress of your project activities.
Tuesday, July 10, 2007
Other Inputs to Project Scope Definition
When defining project scope, you may find that the formal scope planning documents are not always a sufficient source of information. What other sources can you tap into to get the information you need, so you can accurately define project scope?
One source of additional information that contributes to scope definition is outputs from other project planning processes. Outputs of the planning processes in the other knowledge areas can be inputs to defining project scope.
Typically, other planning processes are underway simultaneously with scope planning. The outputs that result from many of these planning processes should be reviewed during scope definition because they often contain valuable information that can be used when defining the project's scope. Oftentimes, the outputs from other planning processes have an impact on the defined scope for a project.
Although you can review other management areas when defining your project scope, you should review four key areas that produce outputs to determine if these outputs have an impact on project scope definition. The four areas you should review are listed below.
One source of additional information that contributes to scope definition is outputs from other project planning processes. Outputs of the planning processes in the other knowledge areas can be inputs to defining project scope.
Typically, other planning processes are underway simultaneously with scope planning. The outputs that result from many of these planning processes should be reviewed during scope definition because they often contain valuable information that can be used when defining the project's scope. Oftentimes, the outputs from other planning processes have an impact on the defined scope for a project.
Although you can review other management areas when defining your project scope, you should review four key areas that produce outputs to determine if these outputs have an impact on project scope definition. The four areas you should review are listed below.
- Project cost management. This area ensures that a project is completed within the approved budget. Since scope definition involves cost estimating, outputs from this area that should be used as inputs to scope definition will focus on resource planning, cost estimating, and cost budgeting.
- Project time management. This area ensures timely project completion. Since project scope definition requires duration estimates, outputs from this knowledge area that should be used as inputs to scope definition focus on activity definition, activity sequencing, and schedule development.
- Project human resource management. This area helps a project manager make the most effective use of team members. Since scope definition requires resource projections, outputs from this area that should be used as inputs to scope definition concern organizational planning and staff acquisition.
- Project quality management. This area ensures that the project will satisfy the needs for which it was undertaken. Since scope definition requires defining deliverables for client satisfaction, outputs from this area will focus on quality planning, quality assurance, and quality control.
Sunday, June 24, 2007
Project Management Constraints
Like any human undertaking, projects need to be performed and delivered under certain constraints. Traditionally, these constraints have been listed as scope, time, and cost. These are also referred to as the Project Management Triangle, where each side represents a constraint. One side of the triangle cannot be changed without impacting the others. A further refinement of the constraints separates product 'quality' or 'performance' from scope, and turns quality into a fourth constraint.
The time constraint refers to the amount of time available to complete a project. The cost constraint refers to the budgeted amount available for the project. The scope constraint refers to what must be done to produce the project's end result. These three constraints are often competing constraints: increased scope typically means increased time and increased cost, a tight time constraint could mean increased costs and reduced scope, and a tight budget could mean increased time and reduced scope.
The discipline of project management is about providing the tools and techniques that enable the project team (not just the project manager) to organize their work to meet these constraints.
Another approach to project management is to consider the three constraints as finance, time and human resources. If you need to finish a job in a shorter time, you can throw more people at the problem, which in turn will raise the cost of the project, unless by doing this task quicker we will reduce costs elsewhere in the project by an equal amount.
Time
For analytical purposes, the time required to produce a deliverable is estimated using several techniques. One method is to identify tasks needed to produce the deliverables documented in a work breakdown structure or WBS. The work effort for each task is estimated and those estimates are rolled up into the final deliverable estimate.
The tasks are also prioritized, dependencies between tasks are identified, and this information is documented in a project schedule. The dependencies between the tasks can affect the length of the overall project (dependency constrained), as can the availability of resources (resource constrained). Time is not considered a cost nor a resource since the project manager cannot control the rate at which it is expended. This makes it different from all other resources and cost categories.
Cost
Cost to develop a project depends on several variables including (chiefly): labor rates, material rates, risk management, plant (buildings, machines, etc.), equipment, and profit. When hiring an independent consultant for a project, cost will typically be determined by the consultant's or firm's per diem rate multiplied by an estimated quantity for completion.
Scope
Requirements specified for the end result. The overall definition of what the project is supposed to accomplish, and a specific description of what the end result should be or accomplish. A major component of scope is the quality of the final product. The amount of time put into individual tasks determines the overall quality of the project. Some tasks may require a given amount of time to complete adequately, but given more time could be completed exceptionally. Over the course of a large project, quality can have a significant impact on time and cost (or vice versa).
Together, these three constraints have given rise to the phrase "On Time, On Spec, On Budget". In this case, the term "scope" is substituted with "spec(ification)".
The time constraint refers to the amount of time available to complete a project. The cost constraint refers to the budgeted amount available for the project. The scope constraint refers to what must be done to produce the project's end result. These three constraints are often competing constraints: increased scope typically means increased time and increased cost, a tight time constraint could mean increased costs and reduced scope, and a tight budget could mean increased time and reduced scope.
The discipline of project management is about providing the tools and techniques that enable the project team (not just the project manager) to organize their work to meet these constraints.
Another approach to project management is to consider the three constraints as finance, time and human resources. If you need to finish a job in a shorter time, you can throw more people at the problem, which in turn will raise the cost of the project, unless by doing this task quicker we will reduce costs elsewhere in the project by an equal amount.
Time
For analytical purposes, the time required to produce a deliverable is estimated using several techniques. One method is to identify tasks needed to produce the deliverables documented in a work breakdown structure or WBS. The work effort for each task is estimated and those estimates are rolled up into the final deliverable estimate.
The tasks are also prioritized, dependencies between tasks are identified, and this information is documented in a project schedule. The dependencies between the tasks can affect the length of the overall project (dependency constrained), as can the availability of resources (resource constrained). Time is not considered a cost nor a resource since the project manager cannot control the rate at which it is expended. This makes it different from all other resources and cost categories.
Cost
Cost to develop a project depends on several variables including (chiefly): labor rates, material rates, risk management, plant (buildings, machines, etc.), equipment, and profit. When hiring an independent consultant for a project, cost will typically be determined by the consultant's or firm's per diem rate multiplied by an estimated quantity for completion.
Scope
Requirements specified for the end result. The overall definition of what the project is supposed to accomplish, and a specific description of what the end result should be or accomplish. A major component of scope is the quality of the final product. The amount of time put into individual tasks determines the overall quality of the project. Some tasks may require a given amount of time to complete adequately, but given more time could be completed exceptionally. Over the course of a large project, quality can have a significant impact on time and cost (or vice versa).
Together, these three constraints have given rise to the phrase "On Time, On Spec, On Budget". In this case, the term "scope" is substituted with "spec(ification)".
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