‫תשע"ז‬/‫אב‬/'‫ח‬
Specification Document
Metrics
Professor Ron Kenett
Tel Aviv Unversity
School of Engineering
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DIMENSIONS OF QUALITY:
•Functionality
•Usability
•Reliability
•Performance
•Serviceability
Hewlett-Packard in the late 1970s, ISO 9126, Information Technology:
Software Produvct Evaluation - Quality Characteristics and
Guidelines for their use., IEEE Software, January 1996.
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Metric
 Understandable.
 Field Tested.
 Economical
 High Leverage.
 Timely.
Measurement
 Setting of standards or goals
 Computation in a timely manner
 Comparison with appropriate standards or goals
 Evaluation of difference to determine required action
 Periodical review of standards, metrics definition, actions.
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‫תשע"ז‬/‫אב‬/'‫ח‬
SOFTWARE SPECIFICATIONS METRICS
-
Completeness
Accuracy
Correctness
Consistency
Redability
Testability
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 Initiator
 Action
 Conditions for
action
 Constrains on
action
 Object of action
 Source of object
 Destination of
(1) Initiator of Action
object
Initiator of Action is the subsystem, function or subfunction whichcauses
the action.
Mechanization
Initiators may be applied, as is frequently true when the action is
passive
but are
Reason
required attributes in all sentences. The initiator is analogous to the subject in English gram
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Parsing Requirements
(2)
Action
There are two types of action : positive and negative.
A positive action is the information processing or transfer of data as performed by the Initi
A negative action is the assignment of constraints to an operation.
(3) Conditions For Action
The conditions for actions are the prerequisite states, activities,
and/or data which are necessary for the action to occur.
(4)
Constraints on Action
The constraints on Action define the boundary conditions enforced on the action after initia
Constraints bound influence, define termination criteria, and specify limits.
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Parsing Requirements - 2
(5) Object of Action
The Object of Action is the subsystem, function, subfunction, or
data item which is being acted on by Initiator via the action.
(6) Source of Object
The source of Object is the immediate subsystem, function,
subfunction, or information structure (data base)
from which the Object originates.
(7) Destination of Object
The Destination of Object is the immediate subsystem, function,
subfunction, or information structure (data base) where the Object is sen
(8) Mechanization of Action
“How is the action accomplished?”.
(9) Reason for Action
Reason for Action provides the rationale for the action.
This information is not strictly necessary, but often helps to
clarify the intent of a requirement sentence.
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“ An RSI shall be provided when either
of the following conditions occur... ”
would be rewritten (for analysis purposes only) as:
[Remote Status Reporting ] shall provide
an RSI when either
of the following conditions occur...
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Referencing Sentence
XX.2.1.1
TYPE
Activity
Initiation
Request
Elapsed
Time
Indicator
INPUTS - The inputs shall be as described in Table XX.2.1-1
SOURCE
UNITS LIMITS ACCURACY FREQUENCY
Application N/A
N/A
N/A
On request
Software
Timer
Control
N/A
N/A
N/A
On request
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‫תשע"ז‬/‫אב‬/'‫ח‬
Parsed translated requirements sentence
XX.2.1.1/1
Request
 Initiator
 Action
 Conditions for action
 Constrains on action
 Object of action
 Source of object
 Destination of object
 Mechanization
 Reason



Function 1 shall input the activity Inititation


from the application software on request
XX.2.1.1/2



Function 1 shall input the elapsed time indicator


from the timer control on request
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‫תשע"ז‬/‫אב‬/'‫ח‬
 Initiator
 Action
 Conditions for action
 Constrains on action
 Object of action
 Source of object
 Destination of object
 Mechanization
 Reason




“In post-attack, the ALCC shall report


the launcher summary status from the OCC


to higher authority via the MF radio

and within TBD seconds of status verification

to prevent a delay in decision resolution.”
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 Initiator
 Action
 Conditions for action
 Constrains on action
 Object of action
 Source of object
 Destination of object
 Mechanization
 Reason




“In post-attack, the ALCC shall report


the launcher summary status from the OCC


to higher authority via the MF radio

and within TBD seconds of status verification

to prevent a delay in decision resolution.”
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‫תשע"ז‬/‫אב‬/'‫ח‬
SPECIFICATION METRICS RAW DATA
N1 - Total number of sentences
N2 - Total number of attributes
N3 - Total number of missing attributes
N4 - Total number of ambiguous attributes
N5 - Total # of missing source attribs
 Initiator
N6 - Total # of missing destination attribs Action
Conditions for action
N7 - Total # of ambiguous source attribs 
 Constrains on action
 Object of action
N8 - Total # of ambiguous destination attrs
Source of object
N9 - Total number of source attributes 
 Destination of object
 Mechanization
N10 - Total # of destination attributes
N11 - Total number of valid attribs (<=9)  Reason
N12 - Total number of TBD
N13 - Total # of missing conditions attribs
N14 - Total # of missing constraints
N15 - Total # of descriptive sentences
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‫תשע"ז‬/‫אב‬/'‫ח‬
SPECIFICATION METRICS DEFINITIONS
SM1 - Missing information = N3/N2
SM2 - Ambiguous information = N4/N2
SM3 - Functional Connectivity =
(N5+N6+N7+N8)/(N9+N10)
SM4 - Attributes presence = N11
SM5 - TBD frequency = N12/N2
SM6 - Missing conditions information = N13/N1
SM7 - Missing constraints = N14/N1
 Initiator
Action
SM8 - Descriptive information = N15/N1 
 Conditions for action
 Constrains on action
 Object of action
 Source of object
 Destination of object
 Mechanization
 Reason
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‫תשע"ז‬/‫אב‬/'‫ח‬




SM1<=1/200 is considered excellent
1/200<SM1<=5/400 is considered fair
5/400<SM1<=5/200 is considered deficient
SM1> 5/200 is considered highly deficient




BLUE - Exceeds all required performance levels; excellen
GREEN - Complies with required performance levels; fair
YELLOW - Contains some deficiencies in performance lev
RED - Contains major deficiencies in performance levels.
Blue and Green are considered accepable
Yellow and Red are considered unacceptable.
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Completeness = 8*(SM1+4*SM2+SM3) + (9-SM4)/5.5 + 2*SM5
Readability
= 40*SM3 + (.33 -SM8)/.25
Accuracy = 20*SM2 + 40*SM5 + 5*SM6 + 0.5*SM7.
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Completeness = 8*(SM1+4*SM2+SM3) + (9-SM4)/5.5 + 2*SM5
Readability
= 40*SM3 + (.33 -SM8)/.25
Accuracy = 20*SM2 + 40*SM5 + 5*SM6 + 0.5*SM7.
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Blue
Green
Yellow
Red
I. Completeness:
SM1 - Missing information
SM2 - Ambiguous information
SM3 - Functional connectivity
SM4 - Attribute presence
SM5 - Fault TBD presence
0
0
0
9
0
1/200 s.
1/200 s.
1/200 s.
6
1/200 s.
2.5/200
2.5/200
2.5/200
4
1/20
5/200
5/200
5/200
3.5
1/2
II. Readability:
SM3 - Functional connectivity
SM8 - Descriptive information
0
1:3 r.
1/200 s.
1:6
2.5/200
1:9
5/200
1:19
III. Accuracy:
SM2 - Ambiguous information
SM5 - Fault TBD presence
SM6 - Missing condition information
SM7 - Missing constraints information
0
0
0
0
1/200 s.
1/200 s.
1/200 s.
1/200 s.
2.5/200
1/20
1/100
1/100
5/200
1/2
1/50
1/50
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