Lecture Notes for CS 325
Requirements Validation and Metrics, 2
February 2000
- requirements Validation
- early
error detection - no bad things
- insure good quality - some good
things
- error types - omission, incorrect facts, inconsistency,
ambiguity
- percentages vary from project to project
-
the classification itself is important to capture statistics
- requirement reviews
- stakeholder reviews - client,
developers, lawyers, ...
- single group or multi-group reviews
- review formality
- review aids - check lists, questions,
previous statistics
- reviews are effective at catching errors
- other review techniques
- automated cross
referencing and general feature extraction
- checks small
scale, internal details - terms defined before use
- applicable
to structure-generating analysis techniques
- effective
- reading - the classic textual review
- scenarios - using
the spec to answer questions about possible uses
- prototyping -
use the spec to build a prototype
- requirements
metrics
- measure characteristics of the requirements
process and document
- more accurately predict the current
project
- improve the process model in general
- size
metrics - a shakey relation between the size of the specification and
the size of the project
- text measurements - paragraphs,
pages
- function points
- oriented towards information
systems
- five i-o types, each weighted by complexity
-
unadjusted (raw) function points (ufp) - weighted sum of i-o types
- complexity adjustment factor (caf) measures environmental
complexity
- 14 characteristics, each weighted by one of six
levels, summed to get N
- caf = 0.65 + 0.01N
-
delivered function points (dfp) = caf*ufp
- reasonably accurate
estimator of project size and cost
- one dfp equals 100
lines of cobol or 80 lines of pl1
- active work to extend
fp to other types of systems
- bang metric - dfd based,
measures bits of data per transform
- quality metrics - how
good is the specification
- srd error count
-
compare with historical data to measure goodness
- determine
latent errors
- change request frequency - both within and
after the specification process
- quality attributes - highly
suspect, but they're numbers
- ambiguity measurements,
cross-product numbers
This page last
modified on 15 March 2000.