DEXi is a computer program for multi-attribute decision making. It is aimed at interactive development of qualitative multi-attribute decision models and the evaluation of options. This is useful for supporting complex decision-making tasks, where there is a need to select a particular option from a set of possible ones so as to satisfy the goals of the decision maker. A multi-attribute model is a hierarchical structure that represents the decomposition of the decision problem into subproblems, which are smaller, less complex and possibly easier to solve than the complete problem.
Further information on DEXi:
DEXi is implemented in Delphi and runs on Microsoft Windows platforms. It can be used free of charge.
The latest DEXi version is 5.01 and is available in two languages:
- DEX is the predecessor of DEXi.
- JDEXi is an open-source Java library implementing: parsing of DEXi models and evaluation of options.
- DEXiTree: a program for pretty drawing of DEXi trees.
- DEXiEval: a command-line utility program for batch evaluation of options using a DEXi model.
DEXi supports two basic tasks:
- the development of qualitative multi-attribute models;
- the application of models for the evaluation and analysis of options.
The models are developed by defining:
- attributes: qualitative variables that represent decision subproblems,
- scales: ordered or unordered sets of symbolic values that can be assigned to attributes,
- tree of attributes: a hierarchical structure representing the decomposition of the decision problem,
- utility functions: rules that define the aggregation of attributes from bottom to the top of the tree of attributes.
In the evaluation and analysis stage, DEXi facilitates:
- description of options: defining the values of basic attributes (terminal nodes of the tree),
- evaluation of options: a bottom up aggregation of option values based on utility functions,
- analysis of options: what-if analysis, “plus-minus-1” analysis, selective explanation and comparison of options,
- reporting: graphical and textual presentation of models, options and evaluation results.
DEXi differs from most conventional multi-attribute decision modeling tools in that it uses qualitative (symbolic) attributes instead of quantitative (numeric) ones. Also, aggregation (utility) functions in DEXi are defined by if-then decision rules rather numerically by weights or some other kind of formula. (However, DEXi does support weights indirectly.)
In comparison with its predecessor DEX, DEXi has a more modern and more convenient user interface. Also, it has better graphical and reporting capabilities, and facilitates the use of weights to represent and assess qualitative utility functions. On the other hand, DEXi is somewhat less powerful than DEX in dealing with incomplete option descriptions: DEX employs probabilistic and fuzzy distribution of values, while DEXi facilitates only the use of crisp or unknown option values.
Editing a decision model
Editing a qualitative attribute scale
Defining decision rules
Editing option descriptions
Option evaluation and analysis
Both DEXi installation packages, Slovene and English, include an English help file.
Documentation in Slovene
An early DEXi User’s Manual is available as:
Jereb, E., Bohanec, M., Rajkovič, V.: DEXi: Računalniški program za večparametrsko odločanje, Moderna organizacija, Kranj, 2003.
Further information on decision analysis, multi-attribute modeling, fundamental DEXi concepts and underlying methods is available in:
Documentation in English
The English help file, which is distributed with the installation, is up-to-date and describes DEXi version 4.01.
The DEXi 5.00 User’s Manual in English is available as:
Bohanec, M.: DEXi: Program for Multi-Attribute Decision Making, User’s Manual, Version 5.00. IJS Report DP-11897, Jožef Stefan Institute, Ljubljana, 2015.
[Also available: a printer-friendly version without hyperlinks.]
M. Bohanec, V. Rajkovič: Večparametrski odločitveni modeli. Organizacija 28(7), 427-438, 1995.
Bohanec, M., Rajkovič, V.: Multi-attribute decision modeling: Industrial applications of DEX. Informatica 23, 487-491, 1999.
Bohanec, M., Zupan, B., Rajkovič, V.: Applications of qualitative multi-attribute decision models in health care, International Journal of Medical Informatics 58-59, 191-205, 2000.
Cestnik, B., Bohanec, M.: Decision support in housing loan allocation: A case study, IDDM-2001: ECML/PKDD-2001 Workshop Integrating Aspects of Data Mining, Decision Support and Meta-Learning: Positions, Developments and Future Directions (eds. Giraud-Carrier, C., Lavrač, N., Moyle, S., Kavšek, B.), Freiburg, 21-30, 2001.
Mladenić, D., Lavrač, N., Bohanec, M., Moyle, S. (eds.): Data mining and decision support: Integration and collaboration. Kluwer Academic Publishers, 2003. Chapters:
- Bohanec, M.: Decision support. 23-35.
- Bohanec, M., Rajkovič, V., Cestnik, B.: Five decision support applications. 177-189.
- Moyle, S., Bohanec, M., Ostrowski, E.: Large and tall buildings: A case study in the application of decision support and data mining. 191-202.
Moyle, S., Ostrowski, E., Bohanec, M.: Knowledge development using data mining: A specific application in the construction industry. Leveraging corporate knowledge (ed. Truch, E.), Gower, 181-197, 2004.
Vintar, M., Grad, J. (ur.): E-uprava: Izbrane razvojne perspektive, Univerza v Ljubljani, Fakulteta za upravo, 2004.:
- Leben, A., Bohanec, M.: Vrednotenje portalov življenjskih situacij, 123-140.
- Bohanec, M.: Odločanje in večparametrsko modeliranje, 205-219.
Bohanec, M., Džeroski, S., Žnidaršič, M., Messéan, A., Scatasta, S., Wesseler, J.: Multi-attribute modeling of economic and ecological impacts of cropping systems, Informatica 28, 387-392, 2004.
Leben, A., Kunstelj, M., Bohanec, M., Vintar, M.: Evaluating public administration e-portals. Information Polity 21(3/4), 207-225, 2006.
Bohanec, M., Messéan, A., Angevin, F., Žnidaršič, M.: SMAC Advisor: A decision-support tool on coexistence of genetically-modified and conventional maize. Proc. Information Society IS 2006, Ljubljana, 9-12, 2006
Verdev. M., Bohanec, M., Džeroski, S.: Decision support for a waste electrical and electronic equipment treatment system. Proc. Information Society IS 2006, Ljubljana, 89-92, 2006
Taškova, K., Stojanova, D., Bohanec, M., Dleroski, S.: A qualitative decision-support model for evaluating researchers. Informatica 31(4), 479-486, 2007.
Omerčević, D., Zupančič, M., Bohanec, M., Kastelic, T.: Intelligent response to highway traffic situations and road incidents. Proc. TRA 2008, Transport Research Arena Europe 2008, 21-24 April 2008, Ljubljana, Slovenia (ed. A. Žnidarič). Ljubljana: DDC svetovanje inženiring: ZAG, Zavod za gradbeništvo Slovenije: DRC, Družba v cestni in prometni stroki Slovenije, 1-6, 2008.
Žnidaršič, M., Bohanec, M., Kok, E.J., Prins, T.W.: Qualitative risk assessment for adventitious presence of unauthorized genetically modified organisms. Proceedings of ISIT 2009, 1st International Conference on Information Society and Information Technologies, Novo mesto: Faculty of information studies. 12.-13.10.2009, Dolenjske Toplice, 7 p., 2009.
Žnidaršič, M., Bohanec, M., Lavrač, N., Cestnik, B.: Project self-evaluation methodology: The Healthreats project case study. Proc. Information Society IS 2009, Ljubljana, 85-88, 2009.
Bohanec, M., Žnidaršič, M.: Izkušnje z večparametrskimi odločitvenimi modeli pri podpori odločanja o gensko spremenjenih organizmih. DAES 2010: Sodobni izzivi menedžmenta v agroživilstvu (ur. Č. Rozman, S. Kavčič), Pivola, 18.-19.3.2010, 29-37, 2010.
Marinič, S., Bohanec, M.: Večparametrsko vrednotenje variant v odvisnosti od konteksta: Model za vrednotenje strešnih kritin Proceedings of the 15th International Conference Information Society IS 2012, 8.-12.10.2012, Ljubljana, 76-79, 2012.
Bohanec, M., Rajkovič, V., Bratko, I., Zupan, B., Žnidaršič, M.: DEX methodology: Three decades of qualitative multi-attribute modelling. Informatica 37, 49-54, 2013.
Alić, I., Siering, M., Bohanec, M.: Hot stock or not? A qualitative multi-attribute model to detect financial market manipulation. eInnovation: Challenges and impacts for individuals, organizations and society, Proceedings of 26th Bled eConference (ed. D.L.Wigand), June 9-13, 2013, Bled, Slovenia, Kranj: Moderna organizacija, 64-77, 2013.
Trdin, N., Bohanec, M., Janža, M.: Decision support system for management of water sources. Proceedings of the 16th International Conference Information Society IS 2013, 7.-11.10.2013, Ljubljana, 118-121, 2013.
Bohanec, M., Aprile, G., Costante, M., Foti, M., Trdin, N.: A hierarchical multi-attribute model for bank reputational risk assessment. DSS 2.0 — Supporting Decision Making with New Technologies (eds. Phillips-Wren, G., Carlsson, S., Respício, A., Brézillon, P.), Amsterdam: IOS Press, ISBN 978-1-61499-398-8, 92-103, 2014.
Mileva Boshkoska, B., Bohanec, M., Boškoski, P., Juričić, Đ.: Copula-based decision support system for quality ranking in the manufacturing of electronically commutated motors. Journal of Intelligent Manufacturing 26, 281-293, 2015.
Bohanec, M., Delibašić, B.: Data-mining and expert models for predicting injury risk in ski resorts. Decision Support Systems V – Big Data Analytics for Decision Making, First International Conference ICDSST 2015, Belgrade, Serbia, May 27-29, 2015, Springer, 46-60, 2015.
DEXi is particularly suitable for solving complex decision problems, which typically involve:
- many (say, 15 or more) attributes,
- many options (10 or more),
- judgment, which prevalently requires qualitative reasoning rather than numerical evaluation,
- inaccurate and/or missing data,
- group decision making, which requires communication and explanation.
For successful application, DEXi requires sufficient resources, particularly expertise and time for developing a DEXi model.
Some typical application areas and decision problems, in which DEX and DEXi have been used so far, are the following:
- Information technology
- evaluation of computers
- evaluation of software
- evaluation of Web portals
- evaluation of projects
- evaluation of proposals and investments
- product portfolio evaluation
- business partner selection
- performance evaluation of companies
- Personnel Management
- personnel evaluation
- selection and composition of expert groups
- evaluation of personal applications for jobs
- Medicine and Health-Care
- risk assessment
- diagnosis and prognosis
- Other Areas
- assessment of technologies
- assessments in ecology and environment
- granting personal/corporate loans
JDEXi (version 3) supports:
- parsing and reading DEXi models from .dxi files or strings (XML format) [constructor Model()]
- obtaining information about model attributes and attribute scales [methods getAttribute*(), getScale*(), …]
- obtaining information about utility functions and decision rules [methods getRule*(), rule*(), function*(), getFunctionString(), …]
- clearing and setting model input values [methods setInputValue(s), …]
- carrying out the evaluation [methods evaluate(), …]
- obtaining evaluation results [methods getOutputValue(s), …]
- modification of decision rules [method getFunctionString()]
JDEXi3 supports only a fairly limited modification of decision rules. DEXi software should be used for any more extensive modification of models.
Authors: Marko Bohanec, Dušan Omerčević, Andrej Kogovšek
This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.
This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
Contents of JDEXi3.zip
bin/ – contains compiled java files
src/ – contains java source files
doc/ – contains javadoc
JDEXi3.jar – JDEXi classes; see javadoc for the list of all classes
JDEXi3Eval.jar – runnable jar for running JDEXi (command-line)
TestJDEXi3.jar and DumpFile.jar – runnable jars for showing the use of JDEXi library (see the sources in src/test/)
lesser.txt – GNU LESSER GENERAL PUBLIC LICENSE
Car.dxi – a sample DEXi file (car selection demo)
readme.html – this file
Runnable jar for running JDEXi application through the command line. It takes 2 mandatory parameters:
- DEXi_file_name: file containing a DEXi model (.dxi)
- Variables: a “;”-separated list of name=value pairs
java -jar JDEXi3Eval.jar Car.dxi "BUY.PRICE=low;MAINT.PRICE=low;#PERS=more;#DOORS=more;LUGGAGE=big;SAFETY=high"
Loads a DEXi model, displays some of its elements (attributes, value scales, decision rules) and evaluates a random decision alternative.
java -jar TestJDEXi3.jar Car.dxi
Loads a DEXi model and prints out all utility functions it contains.
java -jar DumpFunctions.jar Car.dxi
DEXiTree is a companion program to DEXi, aimed at making nice drawings of DEXi’s trees of attributes. Actually, DEXiTree is quite a general and powerful tree-drawing program that:
- offers four different tree-drawing algorithms (called “Distribute”, “Align”, “Walker”, and “QP”);
- draws trees in four different directions (Top-Down, Left-Right, Bottom-Up and Right-Left);
- provides an extensive set of parameters for controlling the appearance of trees and their components.
Please see some DEXiTree screenshots.
DEXiTree is implemented in Delphi and is available for Microsoft Windows. The latest version is 0.94 and is compatible with DEXi 4.01 and later.
Download DEXiTree Version 0.94: DEXiTree094.zip
No installation is required; just unpack the zip file and run DEXiTree.exe.
DEXiTree is typically used in the following steps:
- load (File/Open) a DEXi model from a .dxi file;
- interactively alter DEXiTree’s drawing parameters until you are satisfied with the drawing;
- save the drawing to a file (File/Save as…) or transfer it to other applications through the clipboard (Edit/Copy).
Drawings can be saved and/or transferred in two different graphic formats:
- Windows Enhanced Metafile (.emf) [vector graphic format], or
- Windows Bitmap (.bmp) [bitmap graphic format].
DEXiTree uses its own XML-based “DEXiTree file” format (.dxt) for representing the currently drawn tree of attributes and corresponding drawing parameters, DEXiTree can both load (File/Open) and save (File/Save as…) such files. Loading can be selective so that only a tree structure or only drawing parameters are loaded from file, leaving the other component intact.
See the file DEXiTree.txt for more detailed instructions and conditions of use.
If you use this software for any purpose, an acknowledgment/citation in your product and an informative message to the author would be appreciated.
Copyright © 2007-2015 Marko Bohanec. All rights reserved.
Editing of trees is not supported in DEXiTree. Use DEXi to modify the structure of trees.
DEXiTree has been provided in the hope that it will be useful, but without warranty of any kind.
Any feedback on DEXiTree will be greatly appreciated. Please send your comments, suggestions, bug reports, etc., to Marko Bohanec.
- Marko Bohanec: DEXiTree: A program for pretty drawing of trees. Proc. Information Society IS 2007, Ljubljana, 8-11, 2007.
DEXiEval is a command-line utility program for batch evaluation of options (decision alternatives) using a DEXi model. Basically, DEXiEval reads a DEXi model from a DEXi file and loads option data from another input file. It evaluates these options and writes the evaluation results to output option data files. In one turn, DEXiEval can create several output files in different formats.
No installation is required; just unpack the archive and run DEXiEval.
See the file DEXiEval.txt for detailed instructions and conditions of use.
If you use this software for any purpose, an acknowledgment in your product and an informative message to the author would be appreciated.