Chpt 6 - Project Time Management
What are four types of dependencies or logical relationships in the PDM?
* Finish-to-start (FS) - most common * Finish-to-finish (FF) * Start-to-start (SS) * Start-to-finish (SF) - rarely used
What are the three points of estimation?
* Most Likely (tM) - based on realistic expectations of resources assigned, availability, dependencies on other projects, interruptions * Optimistic (tO) - best-case scenario * Pessimistic (tP) - worst-case scenario Final estimate based on distribution calculation
The inputs of the estimates of activity duration should originate from...
...the person or group on the project team who is most familiar with the nature of the work in the activity
What is a resource calendar?
A calendar that identifies the working days and shifts each resource is available This information is used for estimating resource utilization Information may be at the activity or project level Includes consideration of attributes such as experience or skill level, or locations
What is the Schedule Management Plan?
A component of the project management plan that establishes the criteria and the activities for developing, monitoring, and controlling the schedule. May be formal or informal, highly defined or broadly framed, based on the needs of the project.
What is an activity list?
A comprehensive list that includes all schedule activities required on a project. Includes: * An identifier * Unique title that is descriptive even if displayed outside the project schedule * Scope of work description for each activity in enough detail that team members understand what work is required to be completed
What is a successor?
A dependent activity that logically comes after another activity in a schedule
What is a risk register?
A document in which the results of risk analysis and risk response planning are recorded. Risk events may impact resource selection and availability
What is a project schedule network diagram?
A graphical representation of the logical relationships (aka dependencies) among the project schedule activities. Diagram may be accompanied by a narrative. that describes the basic approach for sequencing. Unusual activity sequences should be fully documented.
What is a milestone list?
A list identifying all project milestones. Indicates if the milestone is mandatory (ex: contract) or optional (ex: from historical information).
What is a milestone?
A significant point or even in a project. Similar structures and attributes to activities but they have zero duration because they represent a moment in time. Milestones may have scheduled dates that influence the way activities are sequenced.
Schedule Network Analysis
A technique that generates the project schedule model Employees various analytical techniques (ex: critical path, critical chain, what-if, resource optimization) to calculate the early and late start and finish dates for the uncompleted portions of the project activities. Some network paths may have points of path convergence or divergence that can be identified and used in schedule compression or other analyses
Outputs from the Estimate Activity Durations process
Activity duration estimates Project document udpates
Outputs from Define Activities process
Activity list Activity attributes Milestone list
What project documents may be updated from the Sequence Activities process?
Activity list Activity attributes Milestone list Risk register
Outputs from the Estimate Activity Resources process
Activity resource requirements Resource breakdown structure Project documents updates
Activity Resource Requirements
Activity resource requirements identify the types and quantities of resources required for each activity in a work package Requirements can be aggregated to determine the estimated resources for each work package and each work period Can include the basis for the estimates and assumptions
What is AON?
Activity-on-node One method for representing a precedence diagram. This is the method used by most PM software
Lead
Amount of time whereby a successor activity can be advanced with respect to a predecessor activity Example: landscaping can begin before the punch list is completed. Would be shown as a FS with a two-week lead
Lag
Amount of time whereby a successor activity will be delayed with respect to a predecessor activity. Example: a technical writing team may begin editing the draft of a large document 15 days after they begin writing it. Shown as SS with a 15 day lag
What is a predecessor?
An activity that logically comes before a dependent activity in the schedule
Parametric Estimating
An estimating technique in which an algorithm is used to calculate cost or duration based on historical data and project parameters Uses a statistical relationship between historical data and other variables to calculate an estimate Durations can be quantitatively determined by multiplying the quantity of work to be performed by labor hours per unit work This method can produce higher levels of accuracy depending upon the sophistication of the underlying data built into the model Can be applied to the total project or segments in conjunction with other methods
What does the Estimate Activity Durations process require?
An estimation of the amount of effort required to complete the activity The amount of available resources estimated to complete the activity Together these are used to approximate the number of work periods (activity duration) to complete the activity using the appropriate project and resource calendars Must document all data and assumptions that support the estimate
Key benefit of the Define Activities process
Break down work packages into activities that provide a a basis for estimating, scheduling, executing, monitoring, and controlling the project work.
Key benefit of the Develop Schedule process
By entering schedule activities, durations, resources, resource availabilities, and logical relationships into the scheduling tool, it generates a schedule model with planned dates for completing project activities.
Group-decision making techniques
By involving a structured group of people who are close to the technical execution of work in the estimation process, additional information is gained and more accurate estimates obtained.
Three-point Estimating
Can improve on single-point activity duration estimates by considering uncertainty and risk
What is published estimating data?
Data like production rates and unit costs for resources
Tools and Techniques for Define Activities process
Decomposition Rolling wave planning Expert judgment
What are activity attributes?
Details about each activity. These evolve over time ex: Activity ID, WBS ID, activity label or name, duration, activity codes, predecessor, successor, leads or lags, resource requirements, assumptions, etc.
Discretionary dependencies
Established based on knowledge of best practices Aka preferred logic, preferential logic, or soft logic Should be fully documented since they can create arbitrary total float values and can limit scheduling options These should be removed and reconsidered when employing fast tracking Determination is made during the sequencing of activities
The Estimate Activity Resources process is closely coordinated with what other process?
Estimates Costs process, part of the Project Cost Management knowledge This coordination could be due to hiring resources
Tools and Techniques of the Estimate Activity Resources process
Expert judgment Alternative analysis Published estimating data Bottom-up estimating Project management software
Tools and Techniques for the Estimate Activity Durations process
Expert judgment Analogous estimating Parametric estimating Three-point estimating Group decision-making techniques Reserve analysis
Tools and Techniques for Plan Schedule Management Process
Expert judgment Analytical techniques Meetings
What is FF?
Finish-to-finish Successor activity cannot finish until a predecessor activity has finished
What is FS?
Finish-to-start Successor activity cannot start until a predecessor activity is finished
Internal dependencies
Have a precedence relationship between project activities Generally within the project team's control Determination is made during the sequencing of activities
Resource Breakdown Structure
Hierarchical representation of resources by category and type. Useful for organizing and reporting project schedule data with resource utilization information Category examples: labor, material, equipment, supplies Type examples: skill level, grade level
What does the schedule management plan do?
Identifies a scheduling method Identifies a scheduling tool Sets the format and establishes criteria for developing and controlling the project schedule Defines how schedule contingencies will be reported and assessed
Key Benefit of Estimate Activity Resources process
Identifies the type, quantity, and characteristics of the resources required to complete the activity which allows more accurate cost and duration estimates.
How can activity resource requirements impact Estimate Activity Durations?
If additional or lower-skilled resources are assigned to an activity, there may be reduced efficiency or productivity due to increased communication, training, and coordination
External dependencies
Involve a relationship between project and non-project activities These are usually outside the project team's control Determination is made during the sequencing of activities
Key benefit of the Sequence Activities process
It defines the logical sequence of work to obtain the greatest efficiency given all project constraints.
What is rolling wave planning?
Iterative planning techniques in which the work to me accomplished in the near term is planned in details, while the work in the future is planned at a higher level. A form of progressive elaboration
Develop Schedule Process overview from PMBOK
Iterative process Schedule model (tool with the data populated) is used to determine planned start and finish dates Dates are based on the accuracy of the input Once dates are determined it is common to have project staff review their activities to confirm the dates present no conflict with resource calendars or assigned activities in other projects
Mandatory dependencies
Legally or contractually required or inherent in the nature of the work Aka hard logic or hard dependencies Determination is made during the sequencing of activities
What are the four dependency attributes?
Mandatory , Discretionary Internal , External Only two can be used at the same time (ex: mandatory external or discretionary internal)
Bottom-up Estimating
Method of estimating project duration or cost by aggregating the estimates of the lower-level components of the WBS (or by activity?) Once estimated, they are aggregated into a total quantity for each activity
What is the PDM?
Precedence Diagramming Model It is a technique used for constructing a schedule model in which activities are represented by nodes and graphically linked by one or more logical relationships to show the sequence in which activities are to be performed.
Tools and Techniques of Sequence Activities process
Precedence diagramming method (PDM) Dependency determination Leads and lags
What information from the project scope statement may be used in the Sequence Activities process?
Product scope description Project deliverables Project constraints Project assumptions
What is PERT?
Program Evaluation and Review Technique. A three-point estimation method
Inputs to Plan Schedule Management Process
Project management plan Project charter EEF OPA
What can the Schedule Management Plan establish?
Project schedule development model - methodology and tool Level of Accuracy - Acceptable range used in determining realistic activity duration Units of Measure - Each unit of measure is defined for each of the resources (ex: (such as staff hours, staff days, or weeks for time measures, or meters, liters, tons, kilometers, or cubic yards for quantity measures) Organizational Procedures Links Project schedule Model Maintenance - Process to update the status and record progress during execution Control Thresholds - Variance thresholds for monitoring. Usually % of deviations Rules of Performance Measurement - EVM or other measurement rules Reporting Formats - Format and frequency Process Descriptions - Of each process
Outputs from Sequence Activities process
Project schedule network diagrams Project document updates
Key benefit of the Plan Schedule Management process
Provides guidance and direction on how the project schedule will be managed throughout the project.
Key benefit of the Estimate Activity Durations process
Provides the amount of time each activity will take to complete, which is a major input into the Develop Schedule process.
Key benefit of the Control Schedule process
Provides the means to recognize deviation from the plan and take corrective and preventive actions and thus minimize risk.
Outputs from Develop Schedule process
Schedule baseline Project schedule Schedule data Project calendars Project management plan updates Project documents updates
Outputs from Plan Schedule Management Process
Schedule management plan
Inputs to the Estimate Activity Durations process
Schedule management plan Activity list Activity attributes Activity resource requirements Resource calendars Project scope statement Risk register Resource breakdown structure EEF OPA
Inputs to Sequence Activities process
Schedule management plan Activity list Activity attributes Milestone list Project scope statement EEF OPA
Inputs to Develop Schedule process
Schedule management plan Activity list Activity attributes Project schedule network diagrams Activity resource requirements Resource calendars Activity duration estimates Project scope statement Risk register Project staff assignments Resource breakdown structure EPP OPA
Inputs to the Estimate Activity Resources process
Schedule management plan Activity list Activity attributes Resource calendars Risk register Activity cost estimates EEF OPA
Inputs to Define Activities process
Schedule management plan Scope baseline EEF OPA
Tools and Techniques for Develop Schedule process
Schedule network analysis Critical path method Critical chain method Resource optimization techniques Modeling techniques Leads and lags Schedule compression Scheduling tool
Management Reserves
Specified amount of project duration withheld for management control purposes and are reserved for unforeseen work that is within the scope of the project "unknown-unknowns" Can also create estimates for these Not included in the baseline but is part of the overall project duration requirements. Use of management reserves may require a change to the schedule baseline
What is SF?
Start-to-finish Successor activity cannot finish until a predecessor activity has started
What is SS
Start-to-start Successor activity cannot start until a predecessor activity has started
Analogous Estimating
Technique for estimating the duration or cost of an activity or a project using historical data from a similar activity or project Uses parameters from a previous, similar project, such as duration, budget, size, weight, and complexity, as the basis for estimating the same parameter or measure for a future project This is a gross value estimating approach. Can be adjusted for known differences in project complexity. Frequently used where there is limited amount of detailed information about the project Generally less costly and less time consuming, but it is also less accurate. Can be used in conjunction with other methods. :) "most reliable when the previous activities are similar in fact and not just in appearance"
Decomposition used in Define Activities process
Technique used for dividing and subdividing the project scope and project deliverables into smaller more manageable parts. Work packages from WBS are decomposed into smaller components called activities that represent the work effort required to complete the work package. Define activities process defines the final outputs as activities rather than deliverables Activity list, WBS, and WBS dictionary can be developed either sequentially or concurrently, with the WBS and WBS dictionary as the basis for development of the final activity list
Contingency Reserves
The estimated duration within the schedule baseline, which is allocated for identified risks that are accepted and for which contingent or mitigation responses are developed "known-unknowns" May be a percentage of the estimated activity duration, a fixed number of work periods, or may be developed by using quantitative analysis (ex: monte carlo simulation) May be separated from the individual activities and aggregated into buffers As more precise information about the project becomes available, the contingency reserve may be used, reduced, or eliminated Contingency should be clearly identified in schedule documentation
What are contingency reserves?
The estimated duration within the schedule baseline, which is allocated for identified risks that are accepted and for which contingent or mitigation responses are developed. Associate with "known-unknowns"
Activity Duration Estimates (output)
The likely number of time periods that are required to complete an activity Do not include lags Mau include some indication of range
Develop Schedule process
The process of analyzing activity sequences, durations, resource requirements, and schedule constraints to create the project schedule model.
Plan Schedule Management process
The process of establishing the policies, procedures, and documentation for planning, developing, managing, executing, and controlling the project schedule.
Estimate Activity Durations process
The process of estimating the number of work periods needed to complete individual activities with estimated resources.
Estimate Activity Resources process
The process of estimating the type and quantities of material, human resources, equipment, or supplies required to perform each activity.
Define Activities process
The process of identifying and documentation the specific action to be performed to produce the project deliverables.
Sequence Activities process
The process of identifying and documenting relationships among the project activities.
Control Schedule process
The process of monitoring the status of project activities to update project progress and manage changes to the schedule baseline to achieve the plan.
good reminder from PMBOK
The project management team determines the dependencies that may require a lead or a lag to accurately define the logical relationship. The use of leads and lags should not replace schedule logic. Activities and their related assumptions should be documented.
Where are the Project Time Management processes and their tools and techniques documented?
The schedule management plan
What is a schedule model?
The scheduling tool populated with project data. A representation of the plan for executing the project's activities including durations, dependencies, and other planning information, used to produce project schedule along with other scheduling artifacts.
Three-point estimate distribution calculations
Triangular Distribution - tE = (tO +tM+tP)/3 Beta Distribution (PERT) - tE = (tO+4tM+tP)/6z
Critical Path Method
Used to estimated the minimum project duration and determine the amount of scheduling flexibility on the logical network paths within the schedule model Calculates the early start, early finish, late start, and late finish dates for all activities without regard for any resource limitations by performing a forward backward pass analysis
Is the duration estimate process progressively elaborated?
Yes