Journal of Organizational and End User Computing, 23(2), 57-80, April-June 2011 57 Copyright © 2011, IGI Global. Copying or distributing in print or electronic forms without written permission of IGI Global is prohibited. Keywords: Auditing, Debugging, Electronic Spreadsheets, End-User Programming, User-Centered Design INTRODUCTION Spreadsheet Prevalence Commercial off-the-shelf spreadsheet programs are one of the most popular end-user program- ming environments in use today (Burnett, Cook, & Rothermel, 2004), and have become ubiqui- tous, and in many cases indispensable software tools throughout industry and within all levels of the business world. Some of the reasons spread- sheets are so popular in end-user computing is Expert and Novice End-User Spreadsheet Debugging: A Comparative Study of Performance and Behaviour Brian Bishop, Dundalk Institute of Technology, Ireland Kevin McDaid, Dundalk Institute of Technology, Ireland ABSTRACT The reliability of end-user developed spreadsheets is poor. Research studies fnd that 94% of ‘real-world’ spreadsheets contain errors. Although some research has been conducted in the area of spreadsheet testing, little is known about the behaviour or processes of individuals during the debugging task. In this paper, the authors investigate the performance and behaviour of expert and novice end-users in the debugging of an experimental spreadsheet. To achieve this aim, a spreadsheet debugging experiment was conducted, with professional and student participants requested to debug a spreadsheet seeded with errors. The work utilises a novel approach for acquiring experimental data through the unobtrusive recording of participants’actions using a custom built VBA tool. Based on fndings from the experiment, a debugging tool is developed, and its effects on debugging performance are investigated. that they are easy to develop and modify, they are highly scalable, and they support numeric data analysis without the specific need to use a ‘behind the scenes’ programming environment. Spreadsheet programs are also extremely flex- ible in terms of size and complexity: the 2007 version of Microsoft Excel can support over 1 million rows and 16 thousand columns per worksheet, with a maximum formula length of 8 thousand characters per cell. It has been estimated that by 2012 there will be 90 million end-users in the U.S. alone and of these 13 million will be end-user programmers; which is significantly higher than the estimated DOI: 10.4018/joeuc.2011040104