軟件行業的質量管理(英文版)(ppt 58頁)

軟件行業的質量管理(英文版)內容提要：
Four Key Quality Concepts：
Reliability
designer must be able to predict how the system will behave:
completeness - does it do everything it is supposed to do? (e.g. handle all possible inputs)
consistency - does it always behave as expected? (e.g. repeatability)
robustness - does it behave well under abnormal conditions? (e.g. resource failure)
Efficiency
Use of resources such as processor time, memory, network bandwidth
This is less important than reliability in most cases
Maintainability
How easy will it be to modify in the future?
perfective, adaptive, corrective
Usability
How easy is it to use?
……

Measurable Predictors of Quality：
Simplicity
the design meets its objectives and has no extra embellishments
can be measured by looking for its converse, complexity:
control flow complexity (number of paths through the program)
information flow complexity (number of data items shared)
name space complexity (number of different identifiers and operators)
Modularity
different concerns within the design have been separated
can be measured by looking at:
cohesion (how well components of a module go together)
coupling (how much different modules have to communicate)
……

SEI and the Capability Maturity Model：
Software quality improvement has led to the establishment of the Software Engineering Institute at Carnegie-Mellon University
Capability Maturity Model (CMM) a framework to assess the maturity level of an organization’s software development and management processes
CMM consists of five levels of maturity as measured by a set of guidelines called the key process areas
Higher levels increase competitiveness, reduce risk
Levels are monotonic: level n includes all the characteristics of all the levels below, n-1, n-2, etc.

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