Formal methods

Macedo H, Oliveira JN.  2015.  A linear algebra approach to OLAP. Formal Aspects of Computing. 27(2):283-307. Abstractart3a10.10072fs00165-014-0316-9.pdf

Inspired by the relational algebra of data processing, this paper addresses the foundations of data analytical processing from a linear algebra perspective. The paper investigates, in particular, how aggregation operations such as cross tabulations and data cubes essential to quantitative analysis of data can be expressed solely in terms of matrix multiplication, transposition and the Khatri–Rao variant of the Kronecker product. The approach offers a basis for deriving an algebraic theory of data consolidation, handling the quantitative as well as qualitative sides of data science in a natural, elegant and typed way. It also shows potential for parallel analytical processing, as the parallelization theory of such matrix operations is well acknowledged.

Oliveira JN.  2014.  Relational Algebra for Just Good Enough Hardware. RAMiCS - 14th International Conference on Relational and Algebraic Methods in Computer Science. 8428:119-138. Abstractramics14.pdf

Device miniaturization is pointing towards tolerating imperfect hardware provided it is “good enough”. Software design theories will have to face the impact of such a trend sooner or later.
A school of thought in software design is relational: it expresses specifications as relations and derives programs from specifications using relational algebra.
This paper proposes that linear algebra be adopted as an evolution of relational algebra able to cope with the quantification of the impact of imperfect hardware on (otherwise) reliable software.
The approach is illustrated by developing a monadic calculus for component oriented software construction with a probabilistic dimension quantifying (by linear algebra) the propagation of imperfect behaviour from lower to upper layers of software systems.


I am professor of Computer Science at the Informatics Department of University of Minho and researcher at HASLab/ INESC TEC. I am also a member of IFIP WG 2.1 (Algorithmic Languages and Calculi) and of the Formal Methods Europe (FME) Association.