DEXi Development
DEXi has been developed in collaboration with the:
Department of Knowledge Technologies, Jožef Stefan Institute, Ljubljana, Slovenia, and
University of Maribor, Faculty of Organizational Sciences, Kranj, Slovenia.
The initial development was financially supported by the Ministry of Education, Science and Sport of the Republic of Slovenia within the Ro (Computer Literacy) Programme (1999-2000).
The development of DEXi started in 1999. The motivation was twofold. First, it was conceived as a successor to DEX, a very successful program for multi-attribute modeling. Until 1999, DEX had been used in several tens of real-life decision situations (see publications on the DEX web page). However, as a MS-DOS program, DEX was becoming outdated and less convenient for its users. Second, in that time in Slovenia, the DEX methodology was taught in several university courses, and there were initiatives to introduce it into secondary schools as well. Thus, there was a strong need for a simple computer program to be used in decision-modeling courses in secondary schools and universities.
Consequently, DEXi’s design is a trade-off between these two requirements. It has a convenient MS Windows user interface, which has been kept as simple as possible. Some advanced DEX features have been deliberately dropped, such as: probability and fuzzy distributions of values, chain attributes, advanced transformations of utility functions, some settings and reports. In order to deal with missing, incomplete or uncertain data, DEXi employs value sets instead of more complex DEX’s value distributions. On the other hand, more emphasis has been put on graphical and reporting capabilities in DEXi. Also, DEXi adds a new functionality to the treatment of attribute weights.
The first version of DEXi was developed in 2000 as part of the project called Expert Systems in Education. The project’s acronym was ESi, where the letter “i” indicated “education” in Slovenian (“izobraževanje”). The name DEXi (pronounced “DEXy”) was coined using the same pattern to mean “DEX for Education”.
In subsequent years, DEXi was increasingly used not only in education, but also in more and more advanced decision-support projects. Some extremely complex decision models were developed in international projects, proving - somewhat surprisingly - that DEXi is suitable not only for education, but also for supporting complex real-life decision problems. Inevitably, in order to address these requirements, DEXi was gradually upgraded with new advanced features, such as new methods for option analysis, import/export features and undo/redo functionality.
Versions
DEXi version 1.00 was released in 2000, with Slovenian user interface only.
DEXi versions 1.01 through 1.04 were gradually released in the period 2001-2006. They addressed only bug fixes and the addition of Slovenian help. There were no major functional additions or improvements.
DEXi version 1.02 with English user interface was released in 2001.
DEXi version 2.00 was released in 2007, introducing a number of additions and improvements:
Slovenian and English user interface for the same functionality,
editing options,
editing utility functions,
importing/exporting options,
exporting utility functions,
report and report settings,
improved DEXi file format,
English help,
installation package,
improved DEXi web page,
bug fixes.
DEXi version 3.00 was released in 2008:
undo/redo functionality,
option analysis functionality,
improved option data entry,
updated English help and DEXi web page,
bug fixes.
DEXi version 3.01 was released in May 2009:
added exporting of attribute tree (two formats: tab-delimited and GML),
bug fixes.
DEXi version 3.02 was released in October 2009:
added model description editor,
added a new operation to join attributes,
added searching functionality,
improved status displays,
bug fixes.
DEXi version 3.03 was released in March 2011:
added descriptions, summary displays and rounding control of utility functions,
added import and copy/paste functionality for utility functions,
new report: Function summary,
exporting reports to tab-delimited files,
extended searching functionality,
bug fixes.
DEXi version 3.04 was released in December 2012:
added html reports,
improved Function Editor: added attribute information display and inconsistency warning,
bug fixes.
DEXi version 4.00 was released in July 2013:
major technical advance by porting source code from Delphi 5 to Delphi 2007, which was enabled by porting the charting component from TeeChart Pro V4 to TeeChart 2012,
consequently, a major reconstruction of charting and reporting modules,
added function status report,
added highlighting of inconsistent decision rules.
DEXi version 4.01 was released in November 2014:
added a 3D chart for displaying utility functions,
controlling screen font size for presentations and better readability,
auto-resizing of table columns,
reconstruction of internal DEX model library,
bug and stability fixes.
DEXi version 5.00 was released in July 2015:
major technical advance by porting source code from Delphi 2007 to Delphi XE7,
granting a “freeware” license for all types of applications,
added scale reversal,
added model protection from editing,
extended function status reports,
bug and stability fixes.
DEXi version 5.01 was released in November 2015:
bug fixes of displaying charts and tables, reversing scales, and performing “±1 Analysis”.
DEXi version 5.02 was released in February 2016:
added functionality: File/Save as… to JavaScript (.js)..
DEXi version 5.03 was gradually developed 2018-19 and not released to public:
added value intervals settings for scales,
fixed computation of normalized weights,
speedup of complex rules generation,
bug, text and stability fixes.
DEXi version 5.04 was released in April 2020:
inconsistency indication for elementary rules,
improved mouse handling in previews.
DEXi version 5.05 was released in May 2021:
added Option generator,
added MSI and portable (.zip) installation packages.