User Interactions in Ontology Mapping Tools

This section details the different types of interactions mapping tools use to allow users to develop mappings. How the user interacts with mapping tools and develops mappings is important when considering the usability of the tools. The interaction needs to be simple and even familiar to use to allow ordinary users to develop mappings with the tool. Table 2-5 outlines six different types of interactions that have or could potentially be used by mapping tools. Details are given on how each interaction modifies the correspondences of mappings, see section 2.1. The first four are interactions which have been implemented in current state of the art mapping tools. The final two are interactions which have not yet been implemented in mapping tools. The first of these interactions is the structure sentence interaction which is the proposed approach of ontogame, see section 2.5.9, and is also an approach used by ontology

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authoring tools, see section 2.4.8. The second interaction is a tagging approach which was identified from the popularity of tagging in web 2.0 websites and applications.

Table 2-5: Types of Interaction that are/can be used in Mapping Tools

Type Understandableᵃ Flexibilityᵇ Actionc

Button Press High None Modification of the confidence measure Construct Lines Medium Low Modification of the confidence measure &

Generation of new correspondences Enter Formulas Low High Modification of the relationship & Generation of new correspondences Data Grid Low Low Generation of new correspondences

Structure Sentences

High None Modification of the relationship

Tagging High High Modification of the relationship ᵃ How simple is the interaction to understand ᵇ Does the interaction allow user specific input c

What action on the correspondence does the interaction allow

2.6.1 Button Press

The button press interaction is widely used in mapping tools to verify candidate correspondences. The interaction is simple and requires the user to verify a candidate correspondence via a button press. If the user verifies the correspondence, the confidence measure is modified to 1 to signify that the correspondence is valid. If the user rejects correspondence, the confidence measure is modified to 0 to signify that the correspondence is invalid. The difficulty of the task is then just reliant on the question and information being asked. There is no flexibility in the interaction and the user can only select one of the options the button(s) present. PROMPT, see section 2.4.2, and OLA, see section 2.4.5, are examples of mapping tools that use the button press interaction.

2.6.2 Construct Lines

The construct lines interaction is also widely used in mapping tools. This interaction is used to verify candidate correspondences and construct new correspondences. The candidate correspondences are presented as correspondences initially displayed with lines between the concepts. The user can remove the line to invalidate a correspondence, i.e. rejects the correspondence. The confidence measure is then modified to 0 to signify that the correspondence is invalid. The user can also append a missed correspondence by joining two concepts with a line. This action generates a new correspondence with the equivalent relation

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between the two concepts the user has selected with a confidence measure of 1. Certain mapping tools allow the line to be weighted which modifies the confidence measure of the correspondence. Furthermore some of the mapping tools combine the construct lines with the enter formulas interaction, see section 2.6.3, to allow the user to input the relationship of the correspondence. This interaction is not as simple as pressing a button and in particular scanning the global structures may cause issues for ordinary users. The interaction offers slight flexibility by allowing the user to weight the confidence measure. COMA++, see section 2.4.2, and CoGZ, see section 2.5.4, are examples of mapping tools that use the drawing lines interaction.

2.6.3 Enter Formulas

The enter formulas interaction is not as commonly used in mapping tools as the previous two interaction types. This interaction allows the users to modify the relationship of the correspondences. Additionally users can also generate new correspondences between concepts with different relationships. The confidence measure will be set to 1 but the mapping tool can uses another interaction to allow the measure to be modified, see section 2.6.2. Furthermore highly specific relations can be generated for the correspondences, such as the uncle relation, if the formulas are provided by the tool. In the author’s opinion, this type of interaction would be too complex for ordinary users to understand. The interaction is highly flexible with even certain mapping tools allowing new formulas to be developed and added by the user. BizTalk [BizTalk 2005] and AlViz, see section 2.4.4, are examples of a mapping tool which uses the enter formulas interaction.

2.6.4 Data Grid

The data grid interaction has been used in the Webscripter mapping tool, see section 2.5.1. With this interaction users are shielded from the complexities of ontologies by only dealing with their instance information. The interaction requires the user to manage correspondences by constructing tables and placing the data within a table. Correspondences with equivalent relationships are then generated between instances which can then be used to generate correspondences between concepts. In the author’s opinion, this kind of interaction will be very tough for ordinary users to grasp as the interaction asks a lot of the user from managing to maintain the data. It would also be a burden for the users as it requires the user to deal with the entire volume of data for mapping.

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2.6.5 Structure Sentences

The structure sentence interaction has been proposed by the Ontogame tool, see section 2.5.9, but has yet to be implemented or evaluated. The interaction allows users to modify the relationship of the correspondences by selecting a sentence, in Ontogame case a word, which best describes the relationship. This is a very similar to the interaction type of natural language interfaces (NLIs), see section 2.4.8. Ordinary users should be able to use this type of interaction as long as sentences used and the information provided is understood by the users. This type of interaction has no flexibility with the users only allowed to select one of the provided sentences.

2.6.6 Tagging

The tagging interaction has not been used by any mapping tool. This type of interaction would allow users to enter their own words for the relationship of a candidate correspondence. Tagging makes the interaction easier for ordinary users as there is an unlimited number of ways to answer and there is no “wrong” choice. However there would be an issue on how to classify the relationship from the tags used. Several popular web sites use tagging. Flickr12 is a site where users can upload their photographs and add tags to organise the photographs and share them with other users. Delicious13 is a site where users upload bookmarks for web pages and add tags to organise the web pages and share them with other users.