Software Evolution Laws

The content of a new software does not have much different from the previous version.

• Conservation of evolution

• Conservation of familiarity

• Conservation of organizational stability

• Conservation of content

The new version of IS software is slower than the exisiting verison. It could be caused by inappropriate handling of change.

• Increase of coupling

• Declining performance

• Declining quality

• Increase complexity

Continuing change

• to avoid become unsatisfactory

• to avoid become not famous

• to increase users

• to improve revenue

Software become more complex due to maintenance activity, additional works may required to reduce the complexity.

• Conservation of organizational stability

• Continuing growth

• . Increase complexity

Product and process measure is closed to normal distribution in the evolution of software

• Feedback system

• Self distributing

• Self Rgulating

• Conservation of organizational stability

Conservation of organizational stability

• the average ineffective global activity rate in an evolving E-type system is invariant

• the average ineffective global activity rate in an evolving E-type system remains constant

• the average effective global activity rate in an evolving E-type system is variant

• the average effective global activity rate in an evolving E-type system remains constant

Multi-level, multi-loop, multi-agent feedback systems that must be treated as such in order to achieve significant improvements over any plausible baseline

• Feedback System

• Continuing Change

• Continuing Growth

• Increase Complexity

Continuuing Growth

• continually upgraded (grow) over time

• continually upgraded (grow) over time to become more complex

• Continually upgraded (grow) over time to meet user needs.

• continually change lead to decline of quality

Which of the following software complied to all Lehman laws of evolution

• Online sales orderig n system

• Operating System

• Standard Calculator Software

• Student registraiton software for a university

Which of the following is perfective maintenance activity?

• Add comments into the source code

• Remove duplicate codes

• Split function with two tasks into multiple functions (or two functions)

• Replace ineffective code with more effcient codes.