Adding deductive logic to a COTS spreadsheet

Abstract

We exploit the spreadsheet metaphor to make deductive problem-solving methods available to the vast population of spreadsheet end users. In particular, we show how the function-based problem-solving capabilities of spreadsheets can be extended to include logical deductive methods in a way that is consistent with the existing spreadsheet "look and feel." The foundation of our approach is the integration of a standard deductive logic system into a successful Commercial-Off-The-Shelf (COTS) spreadsheet. We have demonstrated this by designing and implementing an extension to Excel that manages the integration of Excel and a deductive logic engine based on the World Wide Web Consortium (W3C) standard ontology language OWL + SWRL. IntroductionEnd-user programmers (Nardi 1993) are people who write programs for their own use but are not employed as programmers and are usually not, in fact, trained programmers at all. They can be a teacher, engineer, physicist, secretary, accountant, or manager. They use computers as an essential tool for getting their job done but are not normally interested in programming per se. These end-user programmers currently outnumber professional programmers by more than an order of magnitude. In the U.S. alone, they are estimated to outnumber trained professional programmers by 55 million to 2.75 million in 2005(Boehm et al. 2000. The spreadsheet is the programming language of choice for the overwhelming majority of these end-users. It is widely recognized as one of the few true success stories among systems for end-user programming.Studies have shown (Nardi 1993) that the spreadsheet's key to success is the combination of computational techniques that match the user's tasks (insulating them from the low-level details forced on professional programmers) and a table-oriented interface that serves as a model for users' applications. The structured visual format for data representation turns out to play a crucial role in an end-user's ability to formulate and critique models. We can summarize the spreadsheet's power by the expression computation + presentation. One of these two components alone is not sufficient.

Enhancing Excel business tools with additional relational and recursive capabilities

“…In 2004 DARPA (Defense Advanced Research Projects Agency, EUA) promoted an event (Small Business Innovation Research) in which several deductive spreadsheet have been presented. As a consequence, four projects appeared: NEXCEL [Cervesato, 2007], LESS [Valente et al, 2007], XcelLog [Ramaskrishnan et al, 2007] and [Tallis et al, 2007]. All those systems aimed to enrich Microsoft Excel features.…”

“…In [Tallis et al, 2007] a different approach is proposed, this one using, alternatively, Prolog, Jess (a rule engine that implements the Rete algorithm), or KAON2 (an inference engine that manages Ontologies). We have not found any example or application of this approach, but according to authors, one of its major strengths is the ability to use a semantic representation (OWL, for instance) of the knowledge base.…”

Building Custom Spreadsheet Functions with Python: End-User Software Engineering Approach

“…Research has shown that spreadsheets are a form of code, with spreadsheet users acting as end-user programmers [2]. Excel, specifically, remains one of the most popular end-user programming environments, with its importance in the business world continuing to rise [3]. Microsoft's recent announcement of Python integration within Excel signifies a major step towards enhanced data analysis capabilities within familiar software environments.…”

A Deductive Spreadsheet System for End Users

“…We have developed a system that extends the spreadsheet paradigm with deductive reasoning capabilities [5], [6]. This system extended Microsoft Excel with the OWL and SWRL logic formalism [7], [8].…”