Dra. Aïda Valls Universitat Rovira i Virgili, Tarragona (Catalonia)

Transcription

1 Dra. Aïda Valls Universitat Rovira i Virgili, Tarragona (Catalonia)

2 } Presentation of the ITAKA group } Introduction to decisions with criteria that are organized in a hierarchy } Outranking within hierarchies: ELECTRE-III-H } Examples } Conclusions and future work

3 } Tarragona, Catalonia Created in 1991 World's 66th best university under 50 (THE 2014) } Department of Computer Science and Mathematics: 50 lecturers, 40 PhD students, 13 research groups: Security and privacy in computer systems Artificial Intelligence, robotics and vision Telematic architectures and complex networks Mathematics

4 Group consolidated PhD permanent positions 1 post-doc 4 PhD students + master students Research lines: } Uncertainty, linguistic and semantic models. Especially automatic ontology learning, and ontology-based management of information. } Aggregation operators and MCDA methods. } Personalisation and recommendation. } Expert systems and data mining.

5 } Science and Technology Park of Tourism and Leisure (PCTOO) Applications to Tourism } Tecnatox research center Environmental management and risk evaluation } Research Institute in Health Care Pere Virgili (IISV) Health care applications Current Projects SHADE, funded by the Spanish Government Expert System for medical diagnosis, FIS project, Spanish Government Fuzzy methods for tumor detection in images, part of an European project

6 } Management of multi-valued semantic variables in user profiles, with the assistance of domain ontologies. } Automatic dynamic adaptation of the users preferences based on the analysis of their interaction with the system. } Management of hierarchically structured criteria in decision support systems based on outranking relations. Collaboration of Prof. Slowinski and Dr. Zielniewicz

7 } Management of multi-valued semantic variables in user profiles, with the assistance of domain ontologies. } Automatic dynamic adaptation of the users preferences based on the analysis of their interaction with the system. } Management of hierarchically structured criteria in decision support systems based on outranking relations. Collaboration of Prof. Slowinski and Dr. Zielniewicz

8 User s profile Alternatives Evaluation and Ranking Ranked alternatives User s profile adaptation 8

9 } Management of hierarchically structured criteria in decision support systems based on outranking relations. } The decision maker can decompose the problem into smaller sub-problems at different levels of generality, following a tree structure. Root Intermediate Elementary

10 } We want to obtain a result (a decision) at each non-elementary node of the hierarchy } The procedure is bottom-up Root π Intermediate Elementary π π

11 } Outranking methods are developed in the field of Multiple Criteria Decision Aid (MCDA) } They are based on: Pair-wise comparison of the alternatives, instead of an individual analysis of each one. Do not follow the Dominance Principle. Finding a preference relation (outranking relation) that is according to some social voting rules: 1. Follow the majority opinion 2. Respect the minorities by giving the right of veto

12 } When a DM must compare two alternatives, he will react in one of the three following ways: preference for one of them indifference between them (equivalent) incomparability between them } It is important to distinguish indifference from incomparability. S is a binary relation: asb that represents following statement: a is at least as good as b

13 B.Roy designed a method for choice problems in 1965 ELECTRE: Elimination et choix traduisant la réalité ELECTRE (I and IS) designed for choice problems ELECTRE II (NFS) to rank the alternatives ELECTRE III concerns ranking problems involving pseudo criteria and generates a partial preorder ELECTRE TRI is used for sorting

14 } Example: o Preference (P): bpa o Inverse Preference (P - ): ap - b o Indifference (I ): cid o Incomparability (R): are, grf

15 ELECTRE-III-H relies on the two steps presented in ELECTRE-III. However, the partial concordance and discordances indices are calculated from partial preorders. This method considers weights at each node of the hierarchy. All nodes in the hierarchy can be defined as pseudocriteria by setting indifference (q j ), preference (p j ) and veto thresholds (v j ).

16 } a b c d e f g a I P - R R R R R 1 b P I P P P P P 0 c R P - I I P P P 1 d R P - I I P P P 1 e R P - P - P - I P P 3 f R P - P - P - P - I R 4 g R P - P - P - P - R I 4

17 } e.g., for inverse preference, the partial concordance and discordance indices calculations are as follows:

18 } Destination Marketing Organizations (DMO) are responsible for the promotion of destination brands (e.g. Catalonia, Costa Daurada, Tarragona) } Online tools, such as Websites are crucial for the promotion. They are considered as one of the most important communication tool for destinations. } There does not exist a comprehensive assessment methodology for destination websites in the Tourism industry. } In collaboration with experts (in project CODETUR) we have used ELECTRE-III-H.

19 } Tourist Destination Websites (TDW) are difficult to evaluate because they include multiple and complex factors. } An team of experts (with people of the different regions in Spain) designed an evaluation form (with detailed guidelines), which identifies 123 indicators. } These indicators refer to different quality aspects of the Website, f.i. logos, images, social media, etc. } These indicators were organized in a hierarchical structure of different levels, around 12 main topics.

20 Highlighted indicators/topics are indispensable to the experts. Relevance (weight) of each indicator/topic with regards to the parent node is shown.

21 10 destinations, including cities, regions and even nations were evaluated (in Summer 2012) Destination Andalusia Catalonia Barcelona Madrid Santiago de Compostela Rías Baixas Stockholm Wales Rome Switzerland URL catalunya-act

22 Topic: Interactivity Indicators J1 J2 J3 J4 J5 J6 J7 J8 J9 Scales N, P, Y N, P, Y, E N, P, Y N, P, Y N, F, M N, P, Y N, P, Y N, Y N, Y Weights City / Region 1 Andalusia 0 0, ,5 1 0, Catalonia 0 0,66 0, ,5 0, Barcelona 0 0,33 0,5 1 0, Madrid Santiago de Compostela 1 0,33 0,5 1 0,5 1 0, Rías Baixas 0 0 0, ,5 0, Stockholm 0 0 0,5 0 0,5 0, Wales ,5 0, Rome ,5 0, Switzerland 1 0, ,5 0,5 0,5 0 0

23 } The ELECTRE-III-H method was applied to each node included in the hierarchy, following the structure from the elementary indicators to the root node. } We will show some examples regarding: Usability is referred to the easiness of the webpage to be used and reach the proposed objectives in an efficient, quick, pleasant and attractive way. Accessibility is the easiness to get the web content through different devices for the users. Brand image: created implicitly by means of different communicative acts. Part of the mental image is given by the logotype, slogan and multimedia elements.

24 Usability (53%) Usability and Accessibility aggregated Accessibility (47%) Stock, Rome Anda Mad Bcn Stock Rome Bcn Mad Cat Bcn Stock Mad Sant Cat Switz Switz, Rome Switz Wales Cat Anda Wales Rias Sant Wales Rias Sant Anda Rias

25 Brand Image aggregated Brand (60%) Slogan & Logotype (40%) Switz Switz Switz Anda, Bcn Anda Anda, Wales Sant Bcn Cat Stock Rome Stock Sant Stock Wales Bcn Sant Mad, Wales Rome Rias Cat Cat Mad, Rome Rias Mad Rias

26 } Some of the topics that we will analyze are the following: Usability is referred to the easiness of the webpage to be used and reach the proposed objectives in an efficient, quick, pleasant and attractive way. Accessibility is the easiness to get the web content through different devices for the users. Brand image is created implicitly by means of different communicative acts. Part of the mental image is given by the logotype, slogan and multimedia elements. Positioning refers to the rank position of the web pages in Search Engines, which is an important indicator of web visibility. Architecture is the art and science of structuring and classify Websites.

27 Switz Stock, Rome Bcn Wales Stock Mad Anda Mad Wales, Rome Cat, Rias Positioning Sant Sant Anda Cat Switz Rias Architecture Bcn

28 Stock Bcn Mad, Sant Anda, Switz Wales, Rome Cat Rias Stockholm and Barcelona are presented as the best alternatives globally. These two brands have the most stable ranking over all the 12 topics. Madrid brand may improve the brand image (9th) to try to obtain a better result. Santiago de Compostela may improve its Usability and Accessibility (9th). These are indispensable topics for the experts. Rias Baixas and Catalonia brands needs a deep restructure of their webpages in most of the 12 main topics.

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33 } Touristic Destination Websites are considered as a crucial communication tool for destinations. } Evaluating Websites is a complex task which includes a large number of indicators of different aspects. } ELECTRE-III-H is suitable for providing a preference structure at different levels of generality (and focused on different topics). } Managers may know which are the direct competitors on each aspect, and what to improve to win positions with respect to them.

34 } The evaluation of asb for numerical and ordinal attributes is well known. } And now it is possible for partial prorders. } We are currently developing an extension of ELECTRE- TRI for sorting, in a way that at each level of the hierarchy we can have a different set of categories, appropriate to the meaning of each intermediate criterion. } We are also working on the consideration of semantic attributes in ELECTRE by using ontologies to represent the user s interests.

35 Dra. Aïda Valls Universitat Rovira i Virgili, Tarragona (Catalonia)

36 } } } } Multicriteria Decision Aid and Artificial Intelligence: Links, Theory and Applications, Wiley&Sons, Chapter 4: Preference representation with ontologies. Marín, L., Isern, D., Moreno, A., Valls, A., On-line dynamic adaptation of fuzzy preferences, Special issue On-line fuzzy machine learning and data mining, Information Sciences, vol 2020, n. 20, pp. 5-21, 2013 Borràs, J., Valls, A., Moreno, A., Isern, D., Ontology-based management of uncertain preferences in user profiles, Advances in Computational Intelligence, 14 th Int Conf on Information Processing and Management of Uncertainty in Knowledge-based Systems (IPMU), Part II. Greco et al. (Eds) CCIS 298, pp , Springer-Verlag, Berlin Heidelberg Del Vasto-Terrientes, L., Valls, A., Zielniewicz, P., Slowinski, R., Extending Concordance and Discordance Relations to Hierarchical Sets of Criteria in ELECTRE-III Method, 9 th Modeling Decisions for Artificial Intelligence, Lecture Notes on Artificial Intelligence), vol 7647, 78-89, Springer-Verlag,