Software Metrics
HNC Computing
Unit 8 Quality Management
Sue Hargrave

Control Metrics

Predictor Metrics
Possible relationships between internal
and external software attributes
Maintainability
Number of procedure
parameters
Cyclomatic Complexity
Reliability
Program size in
lines of code
Portability
Number of error
messages
Usability
Length of user manual
Conditions



The internal attribute must be measured
accurately
A relationship must exist between what
we can measure and the external
behavioural attribute
This relationship is understood, has
been validated and can be expressed in
terms of a formula or model
Data collection

Static product analysis

Dynamic product analysis

Process data collation
Automated Data Collection
Instrumented software
system
Usage
Data
Fault
Data
Data collection



Decide what questions need to be
answered
Inform development staff of purpose of
data collection
Manual collection of data during process
development