PM: WBS

Project Management

Work Breakdown Structures

Minder Chen, Ph.D.

CSU Channel Islands

Minder.chen@csuci.edu

WBS and Work Packages

• Create WBS is the process of subdividing project deliverables and project work into smaller, more manageable components.

• The work breakdown structure (WBS) is a deliverableoriented hierarchical decomposition of the work to be executed by the project team to accomplish the project objectives and create the required deliverables, with each descending level of the WBS representing an increasingly detailed definition of the project work. The WBS organizes and defines the total scope of the project, and represents the work specified in the current approved project scope statement.

• The planned work is contained within the lowest level WBS components, which are called work packages .

• A work package can be scheduled, cost estimated, monitored, and controlled.

© Minder Chen, 2012 PM: WBS - 2

Create WBS: Inputs, Tools & Techniques, and Outputs



Sample WBS


Don’t Confusing Effort with Results.

• The WBS was initially defined as a product oriented family tree, however subsequent definitions have introduced more flexibility -- so a WBS can also be deliverable or process oriented.

• Your WBS can be built on nouns or verbs. If the results of your project are primarily verbs, then a verb based or process based WBS may make more sense.

http://www.hyperthot.com/pm_wbs.htm


Creating the Work Breakdown Structure

• An hierarchical outline (map) that identifies the products and work elements involved in a project.

• Defines the relationship of the final deliverable

(the project) to its subdeliverables, and in turn, their relationships to work packages.

• Best suited for design and build projects that have tangible outcomes rather than process-oriented projects.

© Minder Chen, 2012

4 –7 PM: WBS - 7

How WBS Helps the Project Manager

• Facilitates evaluation of cost, time, and technical performance of the organization on a project.

• Provides management with information appropriate to each organizational level.

• Helps in the development of the organization breakdown structure (OBS). which assigns project responsibilities to organizational units and individuals

• Helps manage plan, schedule, and budget.

• Defines communication channels and assists in coordinating the various project elements.


4 –8 PM: WBS - 8

Process-based WBS Completion Criteria

• Status and completion are measurable

• The activity is bounded

• The activity has a deliverable

• Time and cost are easily estimated

• Activity duration is within acceptable limits

• Work assignments are independent t


Work Packages

• A work package is the lowest level of the WBS.

• It is output-oriented in that it:

1. Defines work (what).

2. Identifies time to complete a work package (how long).

3. Identifies a time-phased budget to complete a work package (cost).

4. Identifies resources needed to complete a work package (how much).

5. Identifies a person responsible for units of work

(who).

6. Identifies monitoring points (milestones) for measuring success.


4 –10 PM: WBS - 10

Sample WBS with Major Deliverables


Integrating the WBS with the Organization

• Organizational Breakdown Structure (OBS) depicts how the firm is organized to allocate its work responsibility for a project.

– Provides a framework to summarize organization work unit performance. Identifies organization units responsible for work packages.

– Ties the organizational units to cost control accounts.


Work Package Estimates


WBS Component in WBS Dictionary

• Code of account identifier,

• Description of work,

• Responsible organization,

• List of schedule milestones,

• Associated schedule activities,

• Resources required,

• Cost estimates,

• Quality requirements,

• Acceptance criteria,

• Technical references, and

• Contract information.


Coding the WBS for the Information System

• Levels and elements of the WBS

• Organization elements

• Work packages

• Budget and cost information

• Allows reports to be consolidated at any level in the organization structure.


4 –15 PM: WBS - 15

Direct Labor Budget Rollup


Sample WBS Organized by Phase


Sample WBS Organized by Phase


Process-Oriented vs. Product-Oriented WBS http://www.hyperthot.com/pm_wbs.htm

http://www.hyperthot.com/pm_wbs_concepts.htm


Scope Baseline

• The scope baseline is a component of the project management plan.

• Components of the scope baseline include:

– Project scope statement. The project scope statement includes the product scope description, and the project deliverables, and defines the product user acceptance criteria.

– WBS. The WBS defines each deliverable and the decomposition of the deliverables into work packages.

– WBS dictionary. The WBS dictionary has a detailed description of work and technical documentation for each WBS element.


Verify Scope: ITTO & Data Flow Diagram


Breaking Up Is Hard to Do

• The Story of Cook Ding

• http://www.examiner.com/article/taoism-301-3story-of-cook-ting-the-dextrous-butcher


General Systems Theory: Level of Abstract

(General Systems Theory) does not seek, of course, to establish a single, self contained

'general theory' of practically everything which will replace the theories of particular disciplines.

Such a theory would be almost without content, for we always pay for generality by sacrificing content, and we can say about practically everything is almost nothing. Somewhere however between the specific that has no meaning and the general that has no content there must be, for each purpose and at each level of abstraction, an optimum degree of generality. It is the contention of the General Systems Theorists that this optimum degree of generality is not always reached by the particular sciences."

Source: http://cimru.nuigalway.ie/david/pdf/SE/Slides/Theory.PDF


Design: Cohesion and Coupling

• Divide and Conquer

• Software Design Criteria, plus Reusability

• Modularization: Simple, stable, and clearly defined interface for each module, no need to understand the internal structure or design of a module to use it (i.e., treat it as a black box).

• Low coupling between modules and high cohesiveness within modules


Type of

Coupling

Less interdependence

Less coordination

Less information flow

Normal Coupling

Coupling

Tightness of Coupling

Goodness of Design

Loose Good

Data Coupling (Sending simple parameters)

Stamp Coupling (sending complex data structures)

Control Coupling (sending flags)

Common Coupling (Sharing global data)

Bad

Tight

Content Coupling (Changing code)


Functional Cohesion

• Complex, yes; Cohesive, Yes.

Satellite

Trajectory

A Functionally Cohesive

Module Very High in a Structure Chart

GET

SATELLITE

TRAJECTORY

GET

ELEVATION

Elevation

Times

GET

TIMES

Azimuths

GET

AZIMUTHS

Ranges

GET

RANGES


Scale of Cohesion

Closely related activities that make sense to group them together.

Types of

Cohesion

Visibility

Strength of

Cohesion

Functional Black box Strong

Sequential

Communicational

Procedural

Temporal

Not-quite so black box

Gray box

Logical

Coincidental

Transparent or white box Weak

Maintainability

Good

Bad


The Impact of Module Numbers on Cost

High

Low


Small

Number of Modules

Large

PM: WBS - 28

Decomposition and Integration

• Decomposition ( factoring) refers to the process by which a complex problem or system is broken down into parts that are easier to conceive, understand, program, and maintain.


Testing

• Test plan objectives

– Is thoroughly tested

– Meets requirements

– Does not contain defects

• Test plan covers

– Tools

– Who

– Schedule

– Test result analysis

– What is being tested?

• Test cases

• Automated testing

– Reproducible

– Measurable

Source:

Developing Web Applications with Microsoft

Visual Basic .NET and Microsoft Visual C# .NET


Types of Tests

Test type

Unit test

Integration test

Regression test

Load test

(also called stress test)

Platform test

Objectives

Each independent piece of code works correctly

All units work together without errors

Newly added features do not introduce errors to other features that are already working

The product continues to work under extreme usage

The product works on all of the target hardware and software platforms


Regression and Regression Test

• Regression testing is the process of validating modified parts of the software and ensuring that no new errors are introduced into previously tested code.

• Unit and integration tests form the basis of regression testing. As each test is written and passed, it gets checked into the test library for a regularly scheduled testing run. If a new component or a change to an existing component breaks one of the existing unit or integration tests, the error is called a regression.


Stubs and Drivers

The most common build problem occurs when one component tries to use another component that has not yet been written. This occurs with modular design because the components are often created out of sequence.

Module M

Driver

Stub Module 2

Module 1 Module 2

• Stubs are non-functional components that provide the class, property, or method definition used by the other component. Stubs are a kind of outline of the code you will create later.

• To test two components that need to work together through a third component that has not been written yet, you create a driver. Drivers are simply test components that make sure two or more components work together. Later in the project, testing performed by the driver can

© be performed by the actual component.

PM: WBS - 33

The Myth in The Mythical Man-Month

• Using the man-month as a unit for measuring the size of a job is a dangerous and deceptive myth. It implies that men and months are interchangeable. Men and months are interchangeable commodities only when a task can be partitioned among many workers with no communication among them.

Time versus number of workers —perfectly partitionable task http://www.cs.drexel.edu/~yfcai/CS451/RequiredReadings/MythicalManMonth.pdf


Partitionability

Time versus number of workers — unpartitionable task


Time versus number of workers — partitionable task requiring communication

PM: WBS - 35

Task with Complex Interrelationships

• If each part of the task must be separately coordinated with each other part/ the effort increases as n(n-1)/2, where n is the number of parts.

Time versus number of workers —task with complex interrelationships


PM: WBS

Scope Baseline

Testing

Types of Tests

Regression and Regression Test

Related documents

Products

Support

PM: WBS

Scope Baseline

Testing

Types of Tests

Regression and Regression Test

Related documents

Add this document to collection(s)

Add this document to saved

Suggest us how to improve StudyLib