project scheduling - estimate duration

Project Schedule Planning

  • Phases of Project Management:

    • Initiation

    • Planning

    • Executing

    • Closing

    • Monitoring & Controlling

    • Pre-Project Work

    • Post-Project Work

Processing Steps

  • Define Activities: Based on the Work Breakdown Structure (WBS).

  • Estimate Activity Durations: Specify start and end dates for each activity.

  • Sequence Project Activities: Include milestones to outline the flow of tasks.

  • Assign Resources: Ensure each activity has the necessary resources allocated.

Project Scheduling

Waterfall Process

  • Definition:

    • Linear and sequential approach.

    • Follows a fixed timeline with milestones.

  • Planning:

    • Fix-phased schedule created for all project phases,

    • Tasks, milestones, and clear dependencies accounted for.

  • Stability:

    • Strict adherence to the schedule with buffer time for delays.

    • Fixed roles and resources work sequentially through phases.

Agile Process

  • Definition:

    • Iterative and incremental approach.

    • Driven by the Minimum Viable Product (MVP).

  • Planning:

    • Sprint-based rolling schedule. Short-term plans created at sprint beginnings.

  • Stability:

    • Continuously adjusted based on user feedback.

    • Flexible resource allocation, with adjustments made at each sprint's start.

Estimating Time

  • Methods for Time Estimation:

    • Expert Judgment: Consult subject matter experts.

    • Appropriation Method (Analogous Estimating): Use lessons from similar past projects, along with risks and market factors.

    • Parametric Estimating: Calculated as Time per measured unit. Example:

      • 1 hour/unit x 1000 units = 10,000 hours.

Three-Point Estimates

  • Types of Estimates:

    1. Realistic Estimate (Most Likely - m)

    2. Optimistic Estimate (Best Case - o)

    3. Pessimistic Estimate (Worst Case - p)

  • Calculation Methods:

    • Triangular Distribution:

      • Formula: tE = (o + m + p) / 3

      • Example: tE = (3 + 6 + 8) / 3 = 5.7

    • Beta Distribution:

      • Formula: tE = (o + 4m + p) / 6

      • Example: tE = (3 + 4*6 + 8) / 6 = 5.8

  • WBS Method:

    • Also known as Bottom-up estimating, focuses on detailed activity estimation.