PROCESS IMPROVEMENT

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PART II

• PROCESS IMPROVEMENT

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Chapter 5 Software Process Improvement
Modelszahran

• Objective
• To introduces the quality gurus
• To introduces the concepts of SPI
• To understand the use of sw process models and
  standards

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Chapter 5 Software Process Improvement Models

• Introduction
• Learning from quality gurus
• SPI Models
• Standards and Models for SPI
• Use of SW Process Models and Standards
• Summary

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Introduction

• SPI should be a lifetime habit of SW
  organizations
• Once an organization goes through a complete
  cycle of SPI, it should begin the next one and
  repeat this continuously
• To make continuous SPI a reality in an
  organization, the process culture needs to be
  institutionalized in that organization

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Introduction

• To achieve the status of continuous SPI, process
  awareness, attitudes and behaviors need to be
  ingrained in the organization culture.
• Quality mgt concepts and trends are the roots of
  the sw process maturity and improvement models

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Learning from the Quality Gurus

• Quality gurus

Jurans four steps
Shewharts improvement cycle
Crosbys quality maturity grid
Demings way out of the crisis
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Quality gurus

• Shewharts improvement cycle(1930s)
• Walter shewhart proposed a Plan-Do-Check-Act
  cycle for quality improvement
• 1.Plan
• Define the problem
• State improvement objectives
• 2.Do
• Identify possible problem causes
• Establish baselines
• Test changes

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Quality gurus

• 3.Check
• Collect data
• Evaluate data
• 4.Act
• Implement system change
• Determine effectiveness

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Quality gurus

• Jurans four steps
• Joseph juran suggests a systematic approach to
  control and improve quality
• Emphasizes the mgt of quality at all phases in
  the product lifecycle

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Quality gurus
Quality improvement
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Quality gurus

• Demings way out of the crisis
• Edward demings focus is on the the need for
  mgts long-term commitment to new learning and
  new philosophy in order to achieve transformation
• Suggested fourteen-point plan for achieving the
  transformation towards continuous improvement
  (distribute in class)

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Quality gurus

• Crosbys quality maturity grid
• Phil Crosby stresses the importance of
  involvement and motivation for everyone in the
  organization
• Suggested a Quality Mgt Maturity grid that
  specifies 5 stages of maturity and their
  measurement categories (distribute in class)

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SPI Models

• Many people contributed to the development of the
  sw process maturity movement but, most of the
  credit goes to one individual Watts Humphrey
• Humphreys early work suggested 6 steps for
  organizations to improve their sw capabilities

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SPI Models

• 1. Understand the current status of their
  development process or processes
• 2. Develop a vision of the desired process
• 3. Establish a list of required process
  improvement actions in order of priority
• 4. Produce a plan to accomplish these actions
• 5. Commit the resources to execute the plan
• 6. Restart at step 1

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SPI Models

• 5 maturity levels proposed by Humphrey
• Level 1. Initial
• Level 2. Repeatable
• Level 3. Defined
• Level 4. Managed
• Level 5. optimizing

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SPI Models

• The original sw process maturity model has been
  developed and refined to become the Capability
  Maturity Model (CMM) ? developed by the Software
  Engineering Institute (SEI)
• CMM ? the most popular model for SPI (discuss in
  next chapter )

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Staged Vs Continuous Architecture for SPI Models

• Staged models
• Comprises a number of maturity levels
• Each process area being fixed to a particular
  level
• The key process areas themselves are staged
• Each key process area is the foundation for the
  next process areas and
• Each level represents the foundation for the next
  maturity model
• The result of an assessment againts such models
  usually can be expressed as calibration of the
  organizations maturity
• well-known example ? CMM

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Staged Vs Continuous Architecture for SPI Models

• Continuous Models
• Individual processes progress continually along
  the maturity scale independently of each other
• Example in a project, the Project mgt process
  could be at high maturity level, while the
  configuration mgt process could be at lower
  maturity level
• The result of an assessment against such models
  usually takes the form of a profile for the
  assessed processes
• Example ? ISO/IEC 15504 model

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Staged Vs Continuous Architecture for SPI Models

• Continuous architecture
• General focus
• Building process capability for each process
• Model focus
• A reference model for rating individual processes
  (process capability)

• Staged architectures
• General focus
• Building organizational capability
• Model focus
• Focus on the few issues that need attention to
  progress organizational capability

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Staged Vs Continuous Architecture for SPI Models

• Staged architectures
• Nature of the model
• Describes a roadmap for process improvement
• Describes organizational capability

• Continuous architecture
• Nature of the model
• Describes the terrain of process mgt
• Describes the evolution of individual processes

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Standards and Models for SPI

• There are a number of SPI moels and emerging stds
  developed by international organizations,
  industry consortia, large sw purchasers and sw
  developers
• So far, the most popular model for SPI is the CMM
• The international std ISO/IEC 15504 was developed
  by the International Stds Organization (ISO) for
  SPI under the acronym SPICE

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Standards and Models for SPI
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Use of SW process models and standards

• SPI roadmaps can be the basis for sw process
  assessments, sw process audits, capability
  evaluations and certification of sw
  subcontractors as well as self-improvement
  programmes
• Organizations without in-house sw development
  capability can use the stds and models as a basis
  for developing subcontractor evaluation and
  selection criteria for qualifying their sw
  subcontractors

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Use of SW process models and standards

• Organizations which do have in-house sw
  development capability can use the stds and
  models to design their own sw processes, and to
  develop a self-assessment method. This can be
  used for assessing the organizations sw
  processes and developing a programme for SPI

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Use of SW process models and standards

• Prime contractors who lead a consortium for
  responding to, a specific contract can use the
  stds and models to develop subcontractor
  evaluation and selection criteria for qualifying
  their sw subcontractors. They can also use them
  to assess their own sw processes and develop
  plans for SPI

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Use of SW process models and standards

• Subcontractors and suppliers who develop
  packages, subsystems or components of a system as
  part of a consortium have similar uses to
  customer organizations which have in-house
  development

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Summary

• Quality mgt concepts and trends are the roots of
  the sw process maturity and improvement models
• The concepts of quality preached by the quality
  gurus Deming, Juran and Crosby have influenced
  the SW process improvement approaches
• Watts Humphrey pioneered the adaptation of the
  general quality approaches for software
  engineering
• Humphreys efforts led to the development of the
  SEIs CMM