Software Project Management Lecture # 7

What are we studying today? Chapter 24 - Project Scheduling  Effort distribution  Defining task set for the software project Project types (related topic)  Factors that influence task set selection in a project  A task set example  Defining a task network  Project Scheduling  Timeline charts  Schedule tracking  Earned Value Analysis

Effort Distribution A recommended distribution of effort across software process is often referred to as rule  40% allocated to analysis & design  20% allocated to coding  40% allocated to testing Use the above as a guideline only as each project dictates its own distribution effort

Defining Task Set For The Software Project Task set is a collection of software engineering work tasks, milestones and deliverables that must be accomplished to complete a particular software project. Task sets are different for different types of projects Most organizations encounter following types of projects  Concept development projects Explore some new business concept or application of new technology

Defining Task Set For The Software Project (Contd.)  New application development projects Undertaken as a consequence of specific customer request  Application Enhancement projects Involve modification to functions, performance or interfaces (observable by end-user) in existing software  Application maintenance projects That correct, adapt or extend existing software in ways that may not be obvious to end user  Reengineering projects Undertaken for rebuilding an existing system in whole or part

Factors Influencing Task Set Selection in Projects Size of project Number of potential users Mission criticality Application longevity Stability of requirements Ease of customer/develop communication Maturity of applicable technology Performance constraints Embedded, non embedded characteristics Project staff Reengineering factors These factors also provide an indication of the degree of rigor with which the software process should be applied

A Task Set Example Consider software engineering tasks for a Concept Development project. Such projects are approached by applying the following major tasks: 1.1 Concept scoping determines overall project scope 1.2 Preliminary concept planning Establishes the organization’s ability to undertake work implied by project scope 1.3 Technology risk assessment Evaluates risk associated with the technology to be implemented 1.4 Proof of concept Demonstrates the viability of a new technology in the software context

A Task Set Example (Contd.) 1.5 Concept implementation Implements the concept representation in a manner that can be reviewed by a customer and is used for marketing purposes when a concept must be sold to other customers or management. 1.6 Customer Reaction Concept solicits feedback on a new technology concept and targets specific customer applications

Refinement of Major Tasks The major tasks described earlier may be used to define a macroscopic schedule for project. The macroscopic schedule must be refined to create a detailed schedule. For this each major task is decomposed into a set of subtasks (with related work products and milestones) As an example consider task 1.1 – concept scoping. The refinement is shown on next slide:

Refinement of Major Tasks (Contd.) See page 715

Defining a Task Network Also known as activity network It is a graphic representation of the task flow for a project Displays interdependencies and parallelism Project manager should be aware of those tasks that lie on the critical path

A task set network for ‘concept development’ Enables the team to see the essentially serial nature of the project, but take advantage of parallelism where possible. 1.1 Concept Definition 1.2 Project Planning 1.4a Module A Des/Dev 1.4b Module B Des/Dev 1.5 Integrate & Test 1.6 Concept Demo

Scheduling Two Project Scheduling methods that can be applied to software development:  Program evaluation and review technique (PERT)  Critical Path Method (CPM) Both are driven by Info already developed:  Estimates of effort  A decomposition of product function  The selection of appropriate process model and task set  Decomposition of tasks

Timeline Charts When creating software project schedule, the planner begins with a set of tasks (work breakdown structure) If automated tools are used, the work breakdown is input as a task network Effort, duration and start date are then input for each task As a result of this input, a timeline chart or Gantt chart is generated

Tracking Schedule Accomplished in a no. of ways  Conducting periodic project status meetings in which each team member reports progress & problems  Evaluating results of all reviews conducted throughout the s/w engg process  Determining whether formal project milestones have been accomplished by scheduled date  Comparing actual start date to planned date for each project task  Meeting practitioners to get their assessment of progress to date and problems encountered  Use earned value analysis to assess progress quantitatively

Earned Value Analysis (EVA) A quantitative approach for progress analysis of project Earned value is a measure of progress Steps to determine earned value: 1. The budgeted cost of work scheduled (BCWS) is determined for each work task represented in schedule 2. The BCWS values for all work tasks are summed to derive the budget at completion, BAC BAC = ∑(BCWS k ) for all k tasks 3. Next the value for budgeted cost of work performed (BCWP) is computed. Its value is sum of the BCWS values for all work tasks that have actually been completed by a point in time on the project schedule

EVA (Continued) According to ‘Wilkens’  BCWS represents the budget of activities that were planned to be completed  and BCWP represents the budget of activities that were actually completed Important progress indicators can be computed based on BCWS, BAC, BCWP values  SPI = BCWP/BCWS Schedule performance index indicates efficiency with which project is using scheduled resources. SPI value 1.0 indicates efficient execution of project schedule  SV = BCWP – BCWS Schedule variance, is simply an absolute indication of variance from planned schedule  CPI = BCWP/ACWP Cost performance index value close to 1.0 indicates project is within its defined budget Actual Cost of Work Performed is sum of effort actually expended on work tasks that have been completed by a point in time on project schedule  CV = BCWP – ACWP Cost Variance is an absolute indication of cost savings or shortfall at a particular stage of project 