Defining Interdimensional Dependencies of the Sustainability-Quality Model

Context and Motivation: The growing interest of practitioners in addressing
sustainability in/by software has led us to define the Sustainability-Quality
Assessment Framework (SAF) and associated toolkit, whose usefulness was successfully
evaluated for uncovering relevant sustainability-quality requirements
that contribute to the technical, economic, social, and environmental dimensions
of a software project at hand. However, a key challenge is the identification
of dependencies among quality requirements, framed as relevant design
concerns of a software architecture, due to the multi-dimensional nature of software
sustainability and other extrinsic factors (e.g., stakeholders’ subjectivity
for understanding quality requirements and their relationships).

Objective: With the purpose of providing support to identify the effect of
technical sustainability-quality attributes on the other sustainability dimensions
(i.e, social, environmental and economic), we propose a set of dependency matrixes
as part of the SAF toolkit, and specifically its Sustainability-Quality (SQ)
model.

Method: We first apply a nichesourcing method for identifying the interdimensional
dependencies among quality attributes of the SQ model. As a
result of the nichesourcing study, with 6 experts, three dependency matrixes
were defined and evaluated. Our evaluation focuses on (i) the reliability by applying
the Cohen’s-Kappa technique, and (ii) the sensitivity of each dependency
matrix by means of two hackathons and one single-case experiment conducted
for gathering inter-dimensional dependencies among quality concerns of specific
sustainability-related software projects.

Results: The technical-social dependency matrix was the most reliable, and
the technical-environmental dependency matrix was the less reliable because of
the slight or poor agreement obtained on several dependencies. Regarding our
sensitivity analysis, the results show that the technical-social interdependency

Conclusion: Interdimensional dependency matrices, that obtained a good level
of reliability and acceptable sensitivity, could be used in specific software sustainability
projects for determining the type of effect between sustainability-quality
concerns.