Page 171 - Software and Systems Requirements Engineering in Practice

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C C h a p t e r 5 : Q u a l i t y A t t r i b u t e R e q u i r e m e n t s 137 137
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Quality Attribute Topic Example Quality Attribute Measure
Learnability The average time for a novice user to perform a
specified advanced task for the first time
Operability The frequency with which users make operational
mistakes (attempt to apply the tool to a specified
problem incorrectly)
Attractiveness The frequency with which purchasers choose the
product over a functionally similar product
Time behavior Response time, throughput, and jitter under
specified conditions
Resource utilization Resource consumption (e.g., memory, CPU time,
data transmitted) under a specified workload
Analyzability Average time to diagnose a specified class of bug
Changeability Average time to design, implement, and self-test
a specified type of change to the code
Stability The frequency with which making a specified type
of change introduces unexpected side-effects
Testability The average time to design, implement, and
deploy a specified type of test
Adaptability The average time to adapt the system to a new
type of environment, within a specified range of
environment types, exclusively using specified
adaptation methods
Installability Effort to install the software product in a
specified type of environment
Co-existence Frequency of customer-reported, validated
system failures due to the presence of other
specified, permissible software products in the
same computing environment
Replaceability The list of software products that a given product
is suitable to replace
Effectiveness The proportion of specified use cases that the
software correctly implements
Productivity The proportion of work accomplished to human
effort expended, under specified conditions
Safety The expected monetary cost of harm to people,
business, software, property, or the environment
when the system is used in a specified context
Satisfaction The frequency with which trial users of the software
go on to purchase the software within 30 days
TABLE 5.1 Quality Attributes (continued)