=Paper= {{Paper |id=Vol-1172/CLEF2006wn-ImageCLEF-MartinezFernandezEt2006 |storemode=property |title=MIRACLE Team Report for ImageCLEF IR in CLEF 2006 |pdfUrl=https://ceur-ws.org/Vol-1172/CLEF2006wn-ImageCLEF-MartinezFernandezEt2006.pdf |volume=Vol-1172 |dblpUrl=https://dblp.org/rec/conf/clef/Martinez-FernandezVGM06 }} ==MIRACLE Team Report for ImageCLEF IR in CLEF 2006== https://ceur-ws.org/Vol-1172/CLEF2006wn-ImageCLEF-MartinezFernandezEt2006.pdf
             MIRACLE team report for ImageCLEF IR in CLEF 2006
           Martínez-Fernández, José Luis1, Villena, Julio1,3, García-Serrano, Ana2, Martínez, Paloma1
                                      1
                                        Universidad Carlos III de Madrid
                                     2
                                       Universidad Politécnica de Madrid
                            3
                              DAEDALUS - Data, Decisions and Language, S.A.

                               joseluis.martinez@uc3m.es, jvillena@daedalus.es,
                             agarcia@isys.dia.fi.upm.es, paloma.martinez@uc3m.es

                                                       Abstract
The hypothesis which this paper tries to validate is that text based image retrieval could be improved by the use
of semantic information, by means of an expansion algorithm and a module specifically designed to exclude
common words and negated words from queries. The expansion algorithm applies specification marks to
disambiguate words making use of WordNet [13]. An implementation of this algorithm has been developed for
these experiments. On the other hand, the module in charge of removing common words and detecting negated
words has also been specifically developed for this work. However, after an initial evaluation, none of these
modules led to an improvement in the retrieval quality compared to the baseline experiment, which consists on
the indexing of nouns present in image captions, without no further preprocessing.


Categories and Subject Descriptors
H.3 [Information Storage and Retrieval]: H.3.1 Content Analysis and Indexing; H.3.2 Information Storage; H.3.3
Information Search and Retrieval; H.3.4 Systems and Software. E.1 [Data Structures]. E.2 [Data Storage
Representations]. H.2 [Database Management].


Keywords
Linguistic Engineering, Image Retrieval, Semantic Expansion, WordNet, Word Sense Disambiguation


1   Introduction
The MIRACLE team is made up of three university research groups located in Madrid (UPM, UC3M and UAM)
along with DAEDALUS, a leading company in linguistic technologies in Spain, spin-off of two of these groups,
and the coordinator of the MIRACLE team. This is our fourth participation in CLEF, after years 2003, 2004 and
2005. As well as bilingual, monolingual and robust multilingual tasks [3], the team has participated in the
ImageCLEF [9], Q&A [2], WiQA, iCLEF [16], WebCLEF [12] and GeoCLEF [6] tracks.
Following the structure of previous campaigns, ImageCLEF task has been divided again in several subtasks as
described in [4]. This year, the MIRACLE team has only taken part in the ImageCLEFPhoto task. The main goal
this year for our team was to make use of the new image collection, IAPR, described in [4], and, using the new
textual captions provided, try to make a deep linguistic analysis of these captions in order to build some kind of
semantic representation of the text. This representation uses Charniak’s parser and is also based on WordNet.
The main focus has been put on the implementation of the disambiguation algorithm proposed by [13], with
some consideration to make it more easy to develop. In addition, a basic query analyzer has been added to
produce a linguistic analysis of topics and filter some common expressions and words.
Topics proposed by the organization are divided in three sections, a title, a narrative, i.e. a longer description of
the topic, and a set of images that could be used by a Content Based Image Retrieval (CBIR) system to perform
the search. Image captions in the IAPR collection have different fields and, in the MIRACLE approach, only title
and description fields have been extracted and indexed separately. Taking into account available elements,
several experiments have been executed, which are described in section 4.
Regarding the multilingual dimension of the proposed task, although the IAPR provides captions in English and
German, only the English language has been considered in our experiments. Topics have also been provided in
several languages and the MIRACLE team has submitted runs for Japanese, Simplified Chinese, Russian, Polish
and English.
2   Topic analysis and semantic expansion as implemented for CLEF 2006
Our previous experiences in image retrieval processes [9][10] have shown that, in practical, current indexing
techniques have reached their precision and recall upper limit. To surpass this point, we think that semantic
information should be considered in the retrieval process. For this reason the system developed this year includes
an implementation of a WordNet based semantic expansion method that uses specification marks [13] (adapted
to version 2.1 of WordNet) and a topic analysis module, which is intended to detect common words and to filter
out words introduced by negation expressions.

The semantic expansion method was defined to disambiguate words appearing in WordNet, using the context of
the word to select the correct sense among the set of senses assigned by WordNet. Intuitively, the idea is to
select the sense pertaining to the hyperonym of the word that includes the greater number of senses for the words
appearing in the context. The main objective is to include only the synonyms corresponding to the correct sense
or the word instead of adding all synonyms for all senses of a word. Not every word can be disambiguated by
applying this algorithm. Thus, to increase the number of correctly disambiguated words, three heuristics were
identified. Only one of this heuristics has been included in our implementation, the Definition Heuristic, which
discards senses whose gloss does not include any word present in the context. In CLEF 2005 we tried to use a
variation of this algorithm, which was intended to disambiguate word pairs, but no optimal results were obtained
and, so, this year we decided to use our implementation of the original algorithm. An example of the result of the
expansion process applied to the title of topic 30 is shown in Figure 1.

               WordNet based Semantic Expansion method applied to the title of Topic 30:
                                   "room with more than two beds"
     Filtered nouns      Semantic Expansion without WSD         Semantic Expansion with WSD
     beds, room      beds, furniture, "piece of furniture", beds, furniture, "piece of furniture",
                     "article of furniture", plot, "plot of "article of furniture", room, area
                     ground",     patch,    bottom,    "natural
                     depression", depression, stratum, layer,
                     sheet, "flat solid", surface, foundation,
                     base, fundament, foot, groundwork,
                     substructure, understructure, room, area,
                     way, "elbow room", position, "spatial
                     relation", opportunity, chance, gathering,
                     assemblage
                        Figure 1. Example of the semantic expansion method.

On the other hand, a topic analysis module has been developed to make a deeper selection of terms to search
against the index. This module is used to filter out common words and expressions as well as to detect negation
structures. Thus, phrases like “Relevant images will show” are excluded and words accompanying phrases like
“are not relevant” are expressed with a negation symbol “-“ which is interpreted by the search engine. When
negations are interpreted, not every word taking part in the sentence is excluded, only those words that do not
appear in an affirmative form are negated. An example of the result is shown in Figure 2.

            Original narrative field (topic 50)          Search engine query after topic analysis
     Relevant images will show an interior view of a church, cathedral, view, photos, -images, -
     church or cathedral. Images showing exterior exterior,         -buildings,-fanes
     views of churches or cathedrals are not relevant.
     Interior views of other buildings than fanes are
     not relevant.
                              Figure 2. Example of the topic analysis module.

These are the two main components included in the MIRACLE image retrieval system tested in this campaign.
The following section describes system architecture. For both subsystems, a linguistic analysis of the topic text is
needed. For this purpose, the Charniak’s parser [1] has been integrated. To tokenize the text, i.e. to divide the
text in sentences, the LingPipe tools [7] have been used.

3   System Architecture
The software architecture for the text based image retrieval system is depicted in Figure 3. As can be seen, the
approach is based on the integration of modules that can be optionally activated in order to configure the
different experiments to be submitted. The retrieval process is divided in two tasks: the indexing process, in
charge of building the indexes to be searched. As already mentioned the used search engine is Xapian [18] and
the indexing options have been the usual ones applied by this system, tokenization and stemming of words to be
indexed. The Text Extractor component depicted in Figure 3 takes the XML image captions and extracts the
content of each field. Then, the extracted text is stored in the proper index. During this process, a basic
transliteration of characters is made, to avoid problems with special characters.



    Topics                LingPipe
                                                            Topic
                          Tokenizer
                                                           Analyzer
                                                                                      Search
                                                                                      Engine
                                                                                     (Xapian)



                       Morphosyntactic                    Semantic
                          Analyzer                        Expansor
                         (Charniak)
                                                                                         Index
                                                                                         (Title)        Index
                                                                                                     (Description)
                                                             WordNet                Index (Title +
                                                                                     Description)
    Search Process
    Indexing Process


  IAPR
Collection                                                  Text
                                                          Extractor

                 Figure 3. Architecture for the CLEF 2006 text based image retrieval system

Three different indexes are built: one containing the titles of the image captions, another one containing only the
descriptions present in the image captions and the last one mixing titles and descriptions. The search process is
devoted to the construction of the query to be executed on the previously built indexes. During this process
several tasks are performed:

ƒ     Tokenization. The LingPipe software [7] is used to divide the text in the basic operation unit, which is
      considered to be the sentence. The identification of sentences in the input topic text is always performed.
ƒ     Morphosyntactic Analysis. The Charniak’s parser [1] is used to obtain the morphosyntactic analysis of each
      sentence. These analyses are stored in a database to make them easier to manage and they constitute the
      input for the following processes.
ƒ     Topic Analysis. Topic analysis is applied to every input topic. Two options can be selected: noun, to extract
      only words tagged as nouns during the parsing process, or common, to filter out common expressions like
      “Relevant images will show” and to exclude words introduced by negation structures like “[...] are not
      relevant”. Only words tagged as nouns are considered and the “-“ operator available in Xapian to exclude
      words is used. It is also possible to mark the topic section to be used: title, narrative or both.
ƒ     Semantic Expansion. Optionally, semantic expansion can be applied to the output of the Topic Analysis
      module. This semantic expansion is based on WordNet and the previously described disambiguation method
      is applied to select the synonyms to be included in the query. Words to be excluded from the query are
      ignored by the expansion algorithm and the disambiguation process is performed taking into account the
      scope defined by one sentence.

Different combinations of these modules configure the experiments that have been performed and submitted.
4   Defined experiments
Different modules have been selected to define experiments. Although the IAPR collection is available in two
languages, English and German, only the English target language has been considered. On the other hand, four
different query languages have been tested: English, Japanese, Polish, Russian and Traditional Chinese. Names
and descriptions of runs are included in Table 1. The column “Topic Part” marks the field of the topic that have
been processed: if the label “Title” is included, it means that only the title fragment of the topic has been used,
whereas if the label “Title+Narrative” is given, it means that both fields of the topic have been processed.
Bilingual runs are always marked with the label “Title” because this is the only field provided in topic in
languages distinct than English. Values for the “Topic Analysis” column can be “noun” or ”common” as
described in the previous section. The “Expansion” columns takes ”Yes” value if the Semantic Expansion
module has been used or “No” in other case. Finally, the “Index” column points out which section of the image
caption is used, the title fragment, the description fragment or both.

                                      Table 1: Text-based experiments
                                Topic                           Topic
          Run Name                             Topic Part                        Expansion         Index
                              Language                        Analysis
      miratnntdenen         English         Title+Narrative  Noun               No             Title+Desc.
      miranntdenen          English        Narrative         Noun               No             Title+Desc.
      miranctdenen          English         Narrative        Common             No             Title+Desc.
      miratnctdenen         English         Title+Narrative  Common             No             Title+Desc.
      miratncdenen          English         Title+Narrative  Common             No             Desc.
      miratnndenen          English         Title+Narrative  Noun               No             Desc.
      miranndenen           English        Narrative         Noun               No             Desc.
      mirancdenen           English        Narrative         Common             No             Desc.
      miratctdjaen          Japanese       Title             Common             No             Title+Desc.
      miratntdjaen          Japanese       Title             Noun               No             Title+Desc.
      miratctdplen          Polish         Title             Common             No             Title+Desc.
      miratctdzhsen         Trad. Chinese Title              Common             No             Title+Desc.
      miratntdzhsen         Trad. Chinese Title              Noun               No             Title+Desc.
      miratntdplen          Polish          Title            Noun               No             Title+Desc.
      miratctdruen          Russian        Title             Common             No             Title+Desc.
      miratnndtdenen        English        Title+Narrative   Noun               Yes            Title+Desc.
      miranndtdenen         English        Narrative         Noun               Yes            Title+Desc.
      mirannddenen          English        Narrative         Noun               Yes            Desc.
      miratnnddenen         English         Title+Narrative  Noun               Yes            Desc.
      miratndtdjaen         Japanese       Title             Noun               Yes            Title+Desc.
      miratndtdplen         Polish         Title             Noun               Yes            Title+Desc.
      miratncdtdenen        English        Title+Narrative   Common             Yes            Title+Desc.
      miratncddenen         English         Title+Narrative  Common             Yes            Desc.
      mirancddenen          English        Narrative         Common             Yes            Desc.
      mirancdtdenen         English        Narrative         Common             Yes            Title+Desc.
      miratndtenen          English         Title+Narrative  Noun               Yes            Title
      miratndtdruen         Russian        Title             Noun               Yes            Title+Desc.
      miratndtdzhsen        Trad. Chinese Title              Noun               Yes            Title+Desc.

Besides, two runs combining textual and content based indexing have been submitted. For this purpose, the
content image indexing facilities of Lucene [8] have allowed the construction of an index with image contents.
The three images supplied with the topics have been searched over the image index and the partial results list
combined by adding obtained normalized relevances. The final result list has been combined again with the
textual result list. Table 2 shows the description of these two runs:

                               Table 2: Mixed visual and textual experiments
                               Topic                            Topic
          Run Name                            Topic Part                   Expansion               Index
                             Language                          Analysis
      miratnntdienen        English        Title+Narrative    Noun        No                   Title+Desc.
      miratncdtdienen       English        Title+Narrative    Common      Yes                  Title+Desc.
Obviously, there are more possible combinations, but these ones where considered the most appropriate
according to previous experiences. For example, using only image titles of captions is not useful because a poor
description of each caption can be obtained by the indexer. Besides, if only topic titles are used as the input for
the search process, the characterization of the query built by the search engine is weak and no good results are
usually obtained. Next section provides precision and recall measures for these experiments and a qualitative
explanation for them.

5   Experiment results
Obtained results are somehow discouraging. Table 3 shows the MAP measure for the submitted runs.

                              Table 3: MAP figures for text-based experiments
                           Topic                            Topic
    Run Name                              Topic Part                  Expansion                Index         MAP
                         Language                         Analysis
 miratnntdenen         English         Title+Narrative   Noun         No                   Title+Desc.       0,2009
 miranntdenen          English         Narrative         Noun         No                   Title+Desc.       0,1960
 miranctdenen          English         Narrative         Common       No                   Title+Desc.       0,1875
 miratnctdenen         English         Title+Narrative   Common       No                   Title+Desc.       0,1866
 miratncdenen          English         Title+Narrative   Common       No                   Desc.             0,1375
 miratnndenen          English         Title+Narrative   Noun         No                   Desc.             0,1361
 miranndenen           English         Narrative         Noun         No                   Desc.             0,1352
 mirancdenen           English         Narrative         Common       No                   Desc.             0,1314
 miratctdjaen          Japanese        Title             Common       No                   Title+Desc.       0,1252
 miratntdjaen          Japanese        Title             Noun         No                   Title+Desc.       0,1252
 miratctdplen          Polish          Title             Common       No                   Title+Desc.       0,1075
 miratctdzhsen         Trad. Chinese Title               Common       No                   Title+Desc.       0,1041
 miratntdzhsen         Trad. Chinese Title               Noun         No                   Title+Desc.       0,1041
 miratntdplen          Polish          Title             Noun         No                   Title+Desc.       0,1010
 miratctdruen          Russian         Title             Common       No                   Title+Desc.       0,0909
 miratnndtdenen        English         Title+Narrative   Noun         Yes                  Title+Desc.       0,0172
 miranndtdenen         English         Narrative         Noun         Yes                  Title+Desc.       0,0157
 mirannddenen          English         Narrative         Noun         Yes                  Desc.             0,0157
 miratnnddenen         English         Title+Narrative   Noun         Yes                  Desc.             0,0155
 miratndtdjaen         Japanese        Title             Noun         Yes                  Title+Desc.       0,0103
 miratndtdplen         Polish          Title             Noun         Yes                  Title+Desc.       0,0091
 miratncdtdenen        English         Title+Narrative   Common       Yes                  Title+Desc.       0,0084
 miratncddenen         English         Title+Narrative   Common       Yes                  Desc.             0,0082
 mirancddenen          English         Narrative         Common       Yes                  Desc.             0,0077
 mirancdtdenen         English         Narrative         Common       Yes                  Title+Desc.       0,0072
 miratndtenen          English         Title+Narrative   Noun         Yes                  Title             0,0069
 miratndtdruen         Russian         Title             Noun         Yes                  Title+Desc.       0,0038
 miratndtdzhsen        Trad. Chinese Title               Noun         Yes                  Title+Desc.       0,0034

As can be concluded from these figures, the expansion modules does not produce any improvement, on the
contrary, a decrease of 18 % in MAP is observed. Although the application of expansion methods have not been
definitely proved to increase precision figures, the great decrease produced in these experiments is likely due to a
bug in the implementation. The code and partial evaluations of the expansion algorithm are going to be reviewed
to determine if it is working in the proper way. On the other hand, when the topic analysis module is used to
analyse negation expressions, a decrease in MAP is measured. This is not a strange result, taking into account the
complexity of topics. When the topic and image caption sections used in the retrieval process are regarded, one
can conclude that if greater amounts of text are used in both topic and caption better precision is obtained.
Finally, as observed in previous bilingual retrieval experiments, when the language of topics is different of the
language of the document collection an average 10% decrease in MAP is produced. This is due to the noise
introduced by the translation step needed in these situations.

Table 4 shows MAP values for the experiments where content based image retrieval is used to support textual
retrieval. As concluded in past experiments, content based partial results have no effect in the retrieval precision.
                Table 4: MAP figures for mixed visual and textual retrieval experiments
                        Topic                           Topic
   Run Name                           Topic Part                    Expansion         Index                 MAP
                      Language                         Analysis
miratnntdienen     English         Title+Narrative   Noun          No             Title+Desc.               0,2016
miratncdtdienen    English         Title+Narrative   Common        Yes            Title+Desc.               0,0084


6     Conclusions
One direct conclusion from the previous section is that the experiment considered as the baseline could not be
improved. Although a deeper exploration of results and processes have to be carried out, initially seems to be
due to a improper operation of the expansion module. Besides, it is worth mentioning that there is an 8%
decrease regarding the best MAP obtained last year and in both years experiments were quite similar. This
decrease is the effect of changing the image collection used to test both systems and a clear dependency among
retrieval techniques and image collections used to test those techniques can be concluded. It will be interesting to
compare results for other participants using both test collections.

7     Future work
A conclusive evaluation of the functionality of the implemented expansion algorithm must be performed. The
analysis of obtained results has been started but not still concluded by the time of writing this report. Some
failures in the code have been already detected and corrected. The final goal is to include results of experiments
run with the reviewed expansion algorithm and compared with the actual ones.

Future work in this image retrieval task will try to exploit semantic information obtained from syntactic analysis
and from external resources. Text captions present in the IAPR collection are formed by nominal and
prepositional phrases that could be analysed to extract relations among concepts represented by the headers of
phrases. Some works in this line will be tested in future campaigns.

Acknowledgements
This work has been partially supported by the Spanish R+D National Plan, by means of the project RIMMEL
(Multilingual and Multimedia Information Retrieval, and its Evaluation), TIN2004-07588-C03-01; and by the
Madrid’s R+D Regional Plan, by means of the project MAVIR (Enhancing the Access and the Visibility of
Networked Multilingual Information for Madrid Community), S-0505/TIC/000267.

Special mention to our colleagues of the MIRACLE team should be done (in alphabetical order): José Carlos
González-Cristóbal, Ana González-Ledesma, José Miguel Goñi-Menoyo, Sara Lana-Serrano, Ángel Martínez-
González, Antonio Moreno-Sandoval and César de Pablo-Sánchez.

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