# SAES: An Introduction to Self-Adapting Exploratory Structures
## 5 Integration of Different SAES into a Single Interface  
Although different SAES exist, only dynamic taxonomies can fully support exploratory search. In fact, all the SAES reviewed above, with the exception of extended tag clouds, are monodimensional, and consequently offer very limited or trivial exploration capabilities, akin to the capabilities offered by traditional monodimensional taxonomies. The only possible action is refinement on the branch initially chosen. Although extended tag clouds are multidimensional, and thus support exploration, they do not guarantee completeness of reach. Therefore, strategies other than dynamic taxonomies cannot be used by themselves to provide full and effective exploratory search capabilities. However, this does not mean they are useless. An interesting strategy is to combine one or more of these methods with dynamic taxonomies, thus leveraging its efficient exploration capabilities in order to support different views that can be interesting for the user. One of the most important byproducts of the effort in making dynamic taxonomies a minimal model is the ability to see what the fundamental properties of the model are. The one property that can be used here is the definition of concepts. In dynamic taxonomies, a concept is a label that defines the set of documents classified under it; a concept is a totally abstract entity and the label itself is also abstract and does not need to be textual. From here, an important extension of the model was introduced by [PERSON] [7]: virtual concepts; that is, concepts that are not represented directly, but that are placeholders that interact with external data by providing abstract functions to query external data sources and to summarize subsets of documents. In short, virtual concepts do not only provide a seamless integration with external data sources, such as relational databases, but also provide a way for integrating any SAES into the framework of dynamic taxonomies. Such integration can be done at any level in the taxonomy, but using a SAES as a top-level facet in the taxonomy gives more flexibility in the definition of the interface, since SAES can be placed at top-level in any position in the screen without any problems of user disorientation. Integration of continuous sliders and geographic maps [17; 18] is especially beneficial. Continuous sliders can more effectively deal with number and date ranges than a hierarchical representation of values, both from the query point of view and the summary point of view. Geographic maps are an invaluable device to provide spatial information in many applications, such as real estate, hotel booking, etc. As an example, a user can select desired hotel features (number of stars, free wifi, etc.) and immediately see selected hotels on the map. Conversely, the user can select an area on the map, and have a taxonomic summary of the features for hotels in that area. So, while continuous sliders and maps are virtually useless when used in isolation, their integration with a dynamic taxonomy proves very beneficial. Integration of extended tag clouds into the dynamic taxonomy framework is more questionable. Tag clouds are usually based on metadata tags, and consequently on some sort of classification alternative to the one used by dynamic taxonomies. However, it hardly beneficial to have more than one classification, one of which is taxonomic and the other one flat. In addition, a dynamic taxonomy can be constructed on the basis of metadata tags, making the tag classification moot. A more interesting application derives from extended tag clouds based on textual document terms rather than metadata. In this case, the feedback of popular terms could be effectively used to improve text retrieval queries that are supported, in combination with dynamic taxonomies, for querying textual databases. As remarked above, however, the computation involved might make this approach too expensive for large information bases, and requires further research.