Aree in cui strumenti automatici possono aiutare nell'analisi dei requisiti: individuazione di ambiguità e identificazione di requisiti da testi legali

1. Luisa Mich
Nadzeya Kiyavitskaya

2. 1.
2.
Ambiguity identification in requirements
specifications
Identification of rights and obligations for
regulation compliance
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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3. Natural language requirements specifications
(NL RS)
◦ 79% of requirements documents are couched in
unrestricted NL
◦ majority of developers (64%) think that a higher
level of automation is needed to improve general
efficiency in modeling requirements
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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4. Ambiguity
◦ Is an intrinsic phenomenon of natural language
◦ Means the capability of being understood in two or
more possible senses or ways
◦ May cause:
Implementation of incorrect set of system
requirements
Generation of the wrong test cases for system
verification
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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5. Two step approach to identify ambiguities in
NL RSs:
1. Tool T1 would apply a set of ambiguity measures
to a NL RS in order to identify potentially
ambiguous sentences in the RS
2. Tool T2 would show what specifically is potentially
ambiguous about each sentence in the RS
Final decision is made by a human that may want to
rewrite the sentence
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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6. T1
◦ The tool notifies of potentially ambiguous
sentences by varying their background color
◦ lexical ambiguity at the sentence level
approximates the semantic ambiguity of a
sentence
◦ Uses free dictionaries to identify word lexical
ambiguity
Babylon, Wordnet, WordReference
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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7. T2
◦ Not yet implemented
◦ Preliminary research studies allowed to derive a set
of feasible requirements for T2
T2’s features will include drawing user’s
attention to:
◦
◦
◦
◦
Weak or vague words: similarly, clearly, appropriate
Demonstrative pronouns used as a noun: This is…
Undefined acronyms
Verbs, subjects and verb complements joined by
conjunction
Etc.
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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8. Problem
◦ Law regulates some activities of organizations
◦ To verify if a system is compliant with a
regulation, the requirements imposed by the
regulatory document must be identified
◦ Requirements engineers don’t have expertise in
law and need tool support
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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9. Solution
◦ Develop a systematic process for extracting
requirements from regulations
The semantic parameterization process proposed
by Breaux and Antón
◦ Develop tool support for the process
Implementation of the tool, called Gaius T., based
on this process
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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10. Analysis of regulations with Gaius T.
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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11. Evaluation notes
◦ English and Italian data sets
the HIPAA Privacy Act of U.S.
the Italian Accessibility Law (Stanca act)
◦ The tool was able to largely support humans in
identification of relevant information
◦ Unlike manual annotations, automatic markup is
more consistent
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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12. N. Kiyavitskaya, N. Zeni, L. Mich, D. Berry (2008).
Requirements for tools ambiguity identification and
measurement in natural language requirements
specification, REQUIREMENTS ENGINEERING, 13(3):
207-239. DOI: 10.1007/s00766-008-0063-7
N. Zeni, N. Kiyavitskaya, L. Mich, J.R. Cordy, J.
Mylopoulos (2013). GaiusT: Supporting the
GaiusT:
Extraction of Rights and Obligations for Regulatory
Compliance, REQUIREMENTS ENGINEERING, online
first: ttp://dx.doi.org/10.1007/s00766-0130181-8 DOI: 10.1007/s00766-013-0181-8
Interdisciplinary workshop on requirements analysis Trento, December 15, 2008
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