Study Notes: Introduction to Project Management and Risk Management - Schedule Management

Overview of Project Schedule Management

• Definition: Project schedule management is a knowledge area focused on establishing policies, procedures, and documentation for the planning, development, management, execution, and control of the project schedule.

• Core Objective: The primary goal is to develop a realistic project schedule and establish a schedule baseline.

• General Procedure:

  • First, the project manager (PM) plans how scheduling work will be conducted.

  • Then, work packages from the Work Breakdown Structure (WBS) are decomposed into specific tasks or activities.

  • Activities are sequenced using a network diagram to determine project flow.

  • Activity durations are estimated for each task.

  • Meetings, negotiations, and adjustments occur to ensure the schedule is realistic and agreed upon by stakeholders.

  • Once work begins, schedule performance is measured against the plan, and adjustments/changes are requested as needed.

• Schedule vs. Schedule Baseline:

  • Project Schedule: The "actual" or current scheduled progress of the project.

  • Schedule Baseline: The "planned and approved" version of the project schedule.

  • Schedule Variances: Measured by comparing the actual project schedule against the approved schedule baseline.

Schedule (Time) Management Processes

The sequence of these processes must be followed specifically:

1. Plan Schedule Management: Establishing the approach and procedures.

2. Define Activities: Identifying specific tasks to produce deliverables.

3. Sequence Activities: Identifying and documenting logical relationships between activities.

4. Estimate Activity Durations: Estimating the number of work periods needed.

5. Develop Schedule: Analyzing sequences, durations, resource requirements, and constraints.

6. Control Schedule: Monitoring status and managing changes to the baseline.

Plan Schedule Management

• Key Questions Answered: Who will be involved? What approach will be taken? What processes and procedures will be used?

• Goal: Provide guidance on how the schedule will be managed throughout the project.

• Requirements for Effective Scheduling:

  • Clear scope of work.

  • Decreased time for decision making.

  • Elimination of idle time.

• Schedule Management Plan: This output identifies the scheduling method and tool, setting the format and criteria for developing and controlling the schedule.

• Inputs: Project Management Plan, Project Charter, Enterprise Environmental Factors (EEFs), Organizational Process Assets (OPAs).

• Tools & Techniques: Expert judgment, Analytical techniques (e.g., Critical Path Method, PERT, Resource Leveling), Meetings.

• Outputs: Schedule Management Plan.

Define Activities

• Process: Identifying and documenting the activities the team must perform to complete deliverables. It involves decomposing WBS work packages into activities (tasks).

• Integration: Often combined with creating the WBS and WBS dictionary rather than being treated as a completely separate step.

• Rolling Wave Planning: An iterative planning technique where work for the near term is planned in detail, while future work is planned at a higher level. As the project progresses, the planning horizon is extended and details are refined.

• Key Outputs:

  • Activity List: A comprehensive list including all activities required for the project.

  • Activity Attributes: Details regarding project activities (e.g., ID, name, predecessors, successors, leads, lags, and planned completion dates).

  • Milestone List: Significant events with zero duration ($0$). Initial milestones are documented in the project charter. If a milestone is reached but work is unfinished, the project is not progressing as planned.

• Tools & Techniques: Decomposition, Rolling wave planning, Expert judgment.

Sequence Activities

• Objective: To document the logical dependencies among activities and order work to be performed. This results in a Project Schedule Network Diagram.

• Dependencies vs. Logical Relationships:

  • Dependency: A relationship where the timing or completion of one task depends on another.

  • Logical Relationship: Sequential connections based on inherent characteristics of the work, even without explicit dependencies.

• Four Types of Logical Relationships (PDM):

  • Finish-to-Start (FS): Successor cannot start until the predecessor finishes. (e.g., Construct walls before installing the ceiling). This is the most common.

  • Start-to-Start (SS): Successor cannot start until the predecessor starts. (e.g., Foundation pouring must start before concrete leveling can start).

  • Finish-to-Finish (FF): Successor cannot finish until the predecessor finishes. (e.g., Electrical work cannot finish until drywalling is complete).

  • Start-to-Finish (SF): Successor cannot finish until the predecessor starts. This is rarely used.

• Dependency Determination:

  • Mandatory (Hard Logic): Inherent in the nature of work or required by contract (e.g., design before construction).

  • Discretionary (Soft/Preferred Logic): Based on best practices or team preference (e.g., choosing to furnish Room S before Room R).

  • External: Needs of a party outside the project (e.g., government regulations).

  • Internal: Needs based on internal project control.

Leads and Lags

• Lead: A technique that allows an activity to start before its predecessor is complete (accelerating the successor). Only used in FS relationships.

  • Example: Starting editing after one day of a three-day photo shoot.

• Lag: A directed delay (waiting time) in a successor activity. Can be used in all relationship types.

  • Example: Waiting for cement to dry before applying paint.

Network Diagramming and Path Analysis

• Precedence Diagramming Method (PDM): Also known as Activity on Node (AON). Most used method.

  • Elements: Early Start (ES), Early Finish (EF), Late Start (LS), Late Finish (LF), Duration (D).

  • A forward pass determines ES and EF.

  • A backward pass determines LS and LF.

• Arrow Diagramming Method (ADM): Also known as Activity on Arrow (AOA). Activities are represented by arrows; tails represent the start.

• Path Terminology:

  • Path Divergence: An activity followed by two or more successor activities.

  • Path Convergence: An activity preceded by two or more activities.

• Critical Path: The longest path through the network diagram. It determines the shortest possible duration for the project. Activities on this path have zero float ($0$).

• Float (Slack):

  • Total Float: The amount of time an activity can be delayed from its early start date without delaying the project finish date. Calculated as $LF - EF$ or $LS - ES$.

  • Free Float: The amount of time a task can be delayed without delaying subsequent tasks.

Road Work Network Diagram Case Study

Data Table:

Analyzed Paths:

1. START – A – C – E – F – H – FINISH: $5 + 7 + 6 + 9 + 4 = 31 \, \text{days}$

2. A – C – E – G – H – FINISH: $5 + 7 + 6 + 8 + 4 = 30 \, \text{days}$

3. A – B – D – F – H – FINISH: $5 + 3 + 2 + 9 + 4 = 23 \, \text{days}$

4. A – B – E – G – H – FINISH: $5 + 3 + 6 + 8 + 4 = 26 \, \text{days}$

5. A – B – E – F – H – FINISH: $5 + 3 + 6 + 9 + 4 = 27 \, \text{days}$

Case Study Findings:

• Project Duration: $31 \, \text{days}$

• Critical Path: A – C – E – F – H

• Critical Path Duration: $31 \, \text{days}$

• Float of Activity B: Calculated by identifying the path difference. Since Activity B is not on the critical path, it has float. Based on late start calculations, Activity B late finish is $12$, early finish is $8$. Total float for B is $4 \, \text{days}$.

Estimate Activity Durations: Techniques

• Three-Point Estimating: Expresses estimates in a range (Optimistic (O), Most Likely (ML), Pessimistic (P)).

  • Triangular Distribution (Simple Average): $\frac{O + ML + P}{3}$

  • Beta Distribution (PERT - Weighted Average): $\frac{O + 4ML + P}{6}$

• Analogous Estimation: "Top-down" estimation using historical data from similar past projects. Less costly and time-consuming but potentially less accurate.

• Bottom-up Estimation: Breaking the project into small, detailed tasks and aggregating their estimates. Highly accurate but time-consuming.

• Parametric Estimation: Uses a statistical relationship between historical data and other variables (e.g., $\text{total units} \times \text{time per unit}$).

• Delphi Technique: Gathering opinions from multiple experts anonymously through iterations until consensus is reached.

PERT Calculation Example

• Scenario: Optimistic ($O$) = $9 \, \text{days}$, Pessimistic ($P$) = $18 \, \text{days}$, Most Likely ($ML$) = $12 \, \text{days}$.

• Formula: $\frac{9 + (4 \times 12) + 18}{6} = \frac{9 + 48 + 18}{6} = \frac{75}{6} = 12.5 \, \text{days}$.

• Result: 12.5 days.

Develop Schedule

• Schedule Compression Techniques:

  • Fast Tracking: Performing sequential activities in parallel or partially parallel. Risk increases, but costs generally do not.

  • Crashing: Adding resources to the critical path to shorten duration for the least incremental cost. Examples include overtime, extra resources, or monetary rewards. Costs increase.

• Project Calendar: A calendar of working days and shifts. It defines when schedule activities are worked vs. idle (holidays, weekends).

• Resource Optimization: Adjusting the schedule based on resource availability.

Control Schedule

• Concept: To control is to measure. The PM must measure actual progress against the plan to stay in control.

• Tools: Performance reviews, project management software, modeling techniques, and schedule compression.

• Outputs: Schedule forecasts, change requests, project management plan updates, and organizational process asset updates.

Practice Question Bank Summary

• Question 1: What is the project calendar?

  • Answer: A calendar of working days or shifts that establishes dates for scheduled activities and identifies non-working days.

• Question 2: Landscaping starts $15 \, \text{days}$ before building completion. Relationship?

  • Answer: Finish-to-start (FS) with a $15 \text{-day}$ lead.

• Question 3: Subdividing project scope into smaller components?

  • Answer: Decomposition.

• Question 4: Difference between late and early start of a task?

  • Answer: Total float.

• Question 5: Film editing starts after the shoot ends. Relationship?

  • Answer: Finish-to-Start (FS).