1. Supplementary Slides for
Software Engineering:
A Practitioner's Approach, 5/
e
copyright © 1996, 2001
R.S. Pressman & Associates, Inc.
For University Use Only
May be reproduced ONLY for student use at the university level
when used in conjunction with Software Engineering: A Practitioner's Approach.
Any other reproduction or use is expressly prohibited.
This presentation, slides, or hardcopy may NOT be used for
short courses, industry seminars, or consulting purposes.
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
1

2. Chapter 4
Software Process and Project
Metrics
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
2

3. Measurement &
Metrics
... collecting metrics is too hard ...
it's too time-consuming ... it's too
political ... it won't prove anything ...
Anything that you need to
quantify can be measured in
some way that is superior to
not measuring it at all ..
Tom Gilb
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
3

4. Why do we
Measure?
t To characterize
t To evaluate
t To predict
t To improve
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
4

5. A Good Manager
process Measures
process metrics
project metrics
measurement
product metrics
product
What do we
use as a
basis?
• size?
• function?
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
5

6. Process Metrics
t majority focus on quality achieved as a
consequence of a repeatable or
managed process
t statistical SQA data
¶ error categorization & analysis
t defect removal efficiency
¶ propagation from phase to phase
t reuse data
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
6

7. Project Metrics
t Effort/time per SE task
t Errors uncovered per review hour
t Scheduled vs. actual milestone dates
t Changes (number) and their characteristics
t Distribution of effort on SE tasks
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
7

8. Product Metrics
t focus on the quality of deliverables
t measures of analysis model
t complexity of the design
¶ internal algorithmic complexity
¶ architectural complexity
¶ data flow complexity
t code measures (e.g., Halstead)
t measures of process effectiveness
¶ e.g., defect removal efficiency
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
8

9. Metrics
Guidelines
t Use common sense and organizational sensitivity when
interpreting metrics data.
t Provide regular feedback to the individuals and teams who
have worked to collect measures and metrics.
t Don’t use metrics to appraise individuals.
t Work with practitioners and teams to set clear goals and
metrics that will be used to achieve them.
t Never use metrics to threaten individuals or teams.
t Metrics data that indicate a problem area should not be
considered “negative.” These data are merely an indicator
for process improvement.
t Don’t obsess on a single metric to the exclusion of other
important metrics.
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
9

10. Normalization for
Metrics
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
10

11. Typical Size-Oriented
Metrics
t errors per KLOC (thousand lines of
code)
t defects per KLOC
t $ per LOC
t page of documentation per KLOC
t errors / person-month
t LOC per person-month
t $ / page of documentation
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
11

12. Typical Function-Oriented
Metrics
t errors per FP (thousand lines of code)
t defects per FP
t $ per FP
t pages of documentation per FP
t FP per person-month
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
12

13. Why Opt for FP
Measures?
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
13

14. Computing Function
Points
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
14

15. Analyzing the Information Domain
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
15

16. Taking Complexity into
Account
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
16

17. Measuring
Quality
t Correctness — the degree to which a
program operates according to specification
t Maintainability—the degree to which a
program is amenable to change
t Integrity—the degree to which a program is
impervious to outside attack
t Usability—the degree to which a program is
easy to use
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
17

18. Defect Removal
Efficiency
DRE = (errors) / (errors + defects)
where
errors = problems found before release
defects = problems found after release
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
18

19. Managing
Variation
The mR Control Chart
6
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1 3 5 7 9 11 13 15 17 19
Projects
These courseware materials are to be used in conjunction with Software Engineering: A Practitioner’s Approach,
5/e and are provided with permission by R.S. Pressman & Associates, Inc., copyright © 1996, 2001
19