A Framework for Information Quality
                 Requirements Engineering

                          Mohamad Gharib and Paolo Giorgini

                  University of Trento - DISI, 38123, Povo, Trento, Italy
                       {gharib,paolo.giorgini}@disi.unitn.it



         Abstract. Information Quality (IQ) is a key success factor for the effi-
         cient performance of any organization. Despite this, most Requirements
         Engineering frameworks either ignore or loosely define IQ requirements.
         To this end, we propose a novel conceptual framework for modeling and
         analyzing IQ requirements of the system-to-be.


1      Introduction
The importance of IQ for organizations is out of discussion, and several solutions
for dealing with IQ needs have been proposed in the literature (e.g., integrity
constraints, etc.). However, most of these solutions mainly focus on the technical
aspects of IQ, and they do not solve problems that may rise at organizational
or social levels. More specifically, these techniques do not satisfy the needs of
current complex systems, such as socio-technical systems, where humans and or-
ganizations are integral part of the system along with the technical components
(e.g., smart cities, etc.). At the other hand, we have several Requirements Engi-
neering (RE) approaches that are able to capture the organizational along with
the social needs of the system-to-be (e.g., secure Tropos [1], etc.), but their main
focus is on the functionality of the system, and they either ignore or loosely de-
fine IQ needs. To tackle this problem, we propose a RE framework that is based
on secure Tropos and extends it with concepts for capturing IQ requirements.


2      A Framework for Capturing IQ Requirements
Secure Tropos [1] introduces concepts for modeling actors along with their ob-
jectives, entitlements and capabilities. However, it does not provide concepts for
capturing IQ needs. Thus, we extended its conceptual model with the follow-
ing concepts to model and analyze IQ requirements1 : (1) Goal-information
relations: we provide more refined concepts to capture goals/ information re-
lations, namely: produces, optional read, required read, and sends; (2) Infor-
mation accuracy: we provide trusted production/ trusted provision concepts
to analyze accuracy. For example, information is accurate for read, if it is pro-
duced by trusted actor (it will not produce falsified/ fraud information), and
 1
     For more information about the concepts/formal framework, you can refer to [2,3]




Copyright © 2015 by the authors. Copying permitted for private and academic purposes.
This volume is published and copyrighted by its editors.

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it has been transferred through trusted provision (it will not be intentionally/
unintentionally modified during its transfer). While sender cares only about the
trusted provision to analyze the accuracy of its information; (3) Information
completeness: we provide the part of concept that enables for addressing in-
formation completeness, i.e., information is complete, if it has all its sub parts;
(4) Information timeliness: we provide information volatility, read timeliness,
send timeliness, and information provision time concepts to analyze information
validity. For example, information is valid for read, if its read timeliness is less
than its volatility. While it is valid for send, if its read timeliness at its destina-
tion is less than the required send time, and it is invalid otherwise; (5) Informa-
tion consistency: we provide interdependent readers and read-time concepts
to analyze information consistency, where information is consistent, if all its
interdependent readers have the same read-time, otherwise it is inconsistent.


3     ST-IQ Tool
Our framework is supported by a CASE tool (ST-IQ tool)2 that consists of 3
main parts: (1) GUI that enables for drawing the requirements model; (2) model-
to-text techniques that translate the visual requirements model into Datalog
formal specifications; and (3) automated reasoning support (DLV system3 ) that
is used to verify the correctness and consistency of the requirements model. We
demonstrate the utility of our tool by modeling and analyzing IQ requirements
of case study concerning a main U.S stock market crash (the Flash Crash) [2,3].


4     Ongoing and Future Work
We are working on extending the framework to be able to derive the final IQ
specifications from the requirements model in terms of IQ policies that define
the permitted, forbidden and obligated actors’ activities toward information.
Moreover, we aim to enrich the trust analysis among actors concerning IQ by
relaying on beliefs related to their internal structure (capabilities and intentions).


References
1. Mouratidis, H., Giorgini, P.: Secure tropos: A security-oriented extension of the
   tropos methodology. International Journal of Software Engineering and Knowledge
   Engineering 17(2) (2007) 285–309
2. Gharib, M., Giorgini, P.: Detecting conflicts in information quality requirements:
   the may 6, 2010 flash crash. Technical report, Università degli studi di Trento (2014)
3. Gharib, M., Giorgini, P.: Modeling and reasoning about information quality require-
   ments. In: Requirements Engineering: Foundation for Software Quality (REFSQ15),
   To appear. Springer (2015)

2
    http://mohamadgharib.wordpress.com/
3
    http://www.dlvsystem.com/dlv/




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