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Exploratory computing: designing discovery-driven user experiences
 

Exploratory computing: designing discovery-driven user experiences

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A presentation of my PhD thesis work on exploratory user experiences

A presentation of my PhD thesis work on exploratory user experiences

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    Exploratory computing: designing discovery-driven user experiences Exploratory computing: designing discovery-driven user experiences Presentation Transcript

    • Politecnico di Milano Department of Electronics, Information and Bioengineering Exploratory Computing: designing engines for discovery-driven user experiences Luigi Spagnolo spagnolo@elet.polimi.it December 10, 2012L. Spagnolo Exploratory Computing 1 / 39
    • Outline Information exploration The proposed model The interface Conclusions PublicationsL. Spagnolo Exploratory Computing 2 / 39
    • Information exploration | A different experience Beyond information seeking: making sense, understanding, investigating. • Example: digital library of scientific publications Retrieval task Finding recent, significant publications on a certain research topic and/or by certain authors Exploration • (E.g. scholar) acquiring knowledge about a research domain or specific community: approaches, terminology, main sources of contribution, communication style, etc. • (E.g. university reviewers): Evaluating the contribution of a person/research group (citations, co-authors, metrics, etc.)L. Spagnolo Exploratory Computing 3 / 39
    • Information exploration | Traditional approaches • Hypertext navigation Based on well-engineered information architectures (hierarchies of hyperlinked pages) Static taxonomies fail to scale to large bodies of information Interesting content buried under levels of navigation and information overload • Keyword-based search Arranges content items dynamically according to user needs (expressed by a query) Not very suitable for ill-defined knowledge, non-retrieval goals The user is required to know the terminology • Emerging patterns combine search and browsing → exploratory search Faceted navigation: iterative filtering according to multiple criteria (facets). Becoming a de facto standard. Limit: focus is still mainly on object seeking A more comprehensive approach to the problem is neededL. Spagnolo Exploratory Computing 4 / 39
    • Information exploration | My proposal FELIS: Faceted Exploration for Large Information Spaces A comprehensive, general framework for exploratory user experiences, covering: • Knowledge representation according to multiple item properties (facets) and querying • Widgets and interaction patterns for (semantic) faceted explorations • information visualization strategies to highlight the correlation between item features, supported by exploration metrics to estimate their relevanceL. Spagnolo Exploratory Computing 5 / 39
    • Outline Information exploration The proposed model The interface Conclusions PublicationsL. Spagnolo Exploratory Computing 6 / 39
    • The proposed model | How the exploration works • Over a structured information base Represented according to a more or less complex semantics Basic faceted classification: categories grouped by property Semantic faceted classification: also the properties of related items are used (e.g. browsing artworks by artist’s country) • The user iteratively defines the scope of exploration within the whole space The query specifies the features that information items should or should not possess • The user gets the set of items matching the query plus feedback information about the properties shared by such results • Shared features are also used to refine the query restricting (zoom-in) or enlarging (zoom-out) the scope of the exploration.L. Spagnolo Exploratory Computing 7 / 39
    • The proposed model | FelisQL (1) FelisQL: knowledge modelling and query language • An extension to LISQL (Prof. Ferré, University of Rennes I) • Item representation and querying, definition of faceted taxonomies, syntactic query transformations • Fully translatable into standard RDF and SPARQL Why yet another language?! • user-centric, high level representation of concepts (for both item description and querying) in a concise and natural way (e.g. avoiding unnecessary variables) • easier graphical representation into interface elements • Understandable by domain experts (designers and power users) with lack of expertise in programming Easier configuration and fast prototyping of exploratory applications (future work: computer-aided design tools)L. Spagnolo Exploratory Computing 8 / 39
    • The proposed model | FelisQL (2) Examples of representable queries: • Publications authored by foreign PhD students at Politecnico di Milano, with the support of a professor from a foreign university a publication and a u t h o r : [ a ’PhD student ’ and c o u n t r y : not Italy ] at a f f i l i a t i o n : ’Politecnico di Milano ’ , [ a professor ] at a f f i l i a t i o n : c o u n t r y : not Italy • Italian painters authors of landscapes in XIX or XX century a painter and c o u n t r y : ’Italy ’ and a u t h o r of [ s u b j e c t : [ a landscape ] and p e r i o d : "XIX century " or "XX century " ]L. Spagnolo Exploratory Computing 9 / 39
    • The proposed model | FelisQL (3) Example of description: ’Monna Lisa ’ [ a painting and s u b j e c t : [ a woman and h a i r : c o l o r : " black " ] , [ a landscape ] and a u t h o r : ’Leonardo Da Vinci ’ [ a painter and an engineer and a scientist and n a t i o n a l i t y : " Italian " and b i r t h : [ p l a c e : Vinci [ a city and part of ’Province of Florence ’ ] and y e a r : 1 4 5 2 ] and d e a t h : [ p l a c e : Amboise [ a city and part of ’Indre et Loire ’ ] and y e a r : 1 5 1 9 ] ] ... ]L. Spagnolo Exploratory Computing 10 / 39
    • The proposed model | FelisQL (4) Query transformations: syntactic operations (supported out by hyperlinks in the interface) allowing to move from a stage to another of the exploration, e.g.: • Focus change: selecting the specific sub-expression (focus) of the query at which appending a new restriction a painting and artist : [a woman] focus a woman • And-insertion: adding a new restriction in conjunction at the selected focus a painting and artist : [a woman] and country : ‘UK’ • Or-insertion adding a new restriction in disjunction at the selected focus a painting and artist : [a woman and country : ‘UK’] or country : ‘USA’ • Exclusion: selecting items that do not have certain features a painting and artist : [a woman and country : ‘UK’ or ‘USA’] exclude subject : [a portrait]L. Spagnolo Exploratory Computing 11 / 39
    • The proposed model | Relevance measures (1) Providing feedback about the interestingness of a item feature C w.r.t. the whole information space Ω or the specific context of exploration represented by the query q Notation: | {C }Ω | is the number of items in Ω matching C . • Relative count: most common measure µcount (C, q) = q and C Ω • Frequency: the percentage of items that match the query q and also the feature C µcount (C, q) µf req (C, q) = |{q}Ω | Corresponds to the confidence of the association rule q → C, i.e. conf(q → C)L. Spagnolo Exploratory Computing 12 / 39
    • The proposed model | Relevance measures (2) • Recall: the percentage of items that match the query q among those matching the feature C µcount (C, q) µrecall (C, q) = q C Ω Corresponds to conf(C → q) Measures peculiarity, i.e. how much C is typical in the context of q (and less likely to be found elsewhere) • Highlighting significant correlations between a feature C and the query q estimating how much both frequency and recall diverge from their expected values if C and q where statistically independentL. Spagnolo Exploratory Computing 13 / 39
    • The proposed model | Relevance measures (3)Civilization orperiods related toarchaeologicalvenues in Italy. • Font size: frequency/count of terms • Bar charts: frequency and recall When no filter is set, the recall is 100%.Demo available at: http://hoc12.elet.polimi.it/metrics/archeo/L. Spagnolo Exploratory Computing 14 / 39
    • The proposed model | Relevance measures (4)Civilization orperiods related toarchaeologicalvenues in NorthernItaly. • Coloured tags: significant postive/negative frequency (text color) or recall (background) • Bar charts: Detail and deviance from expected.L. Spagnolo Exploratory Computing 15 / 39
    • The proposed model | Relevance measures (5)Civilization orperiods related tomuseums inSouthern Italy.L. Spagnolo Exploratory Computing 16 / 39
    • The proposed model | Relevance measures (6) Joint relevance measure: measuring how much the features Ca and Cc are correlated in the context of the query q • E.g. Lift: q and Ca and Cb Ω νlif t (Ca , Cb , q) = q and Ca · q and Cb Ω ΩL. Spagnolo Exploratory Computing 17 / 39
    • The proposed model | Relevance measures (7)Correlations betweenconcepts representingCivilization orperiods related toarchaeologicalvenues in CentralItaly. • Node: count (size) and significant frequency (color) • Edge size and colour: Lift measure between pairs of conceptsL. Spagnolo Exploratory Computing 18 / 39
    • The proposed model | Relevance measures (8)Correlations betweenconcepts representingCivilization orperiods related toarchaeologicalvenues in CentralItaly. • Selection of a node (filtering preview)L. Spagnolo Exploratory Computing 19 / 39
    • The proposed model | Difference metrics (1) Providing feedback about how much the relevance measure of a item feature C changes when moving from a new stage of the texploration, e.g. from query qn−1 to query qn • Difference metrics can be applied to the result of any query trasformation • providing additional clues of possible correlations to be investigated • Absolute frequency difference: ∆f req (C, qn ) = µf req (C, qn ) − µf req (C, qn−1 ) • Relative frequency difference: ∆f req (C, qn ) δf req (C, qn ) = µf req (C, qn )L. Spagnolo Exploratory Computing 20 / 39
    • The proposed model | Difference metrics (2) Bipolar bar chart • showing frequency differences for types of archaeological venue • previous query: location : ‘Southern Italy’ or ‘Insular Italy’ • current query: location : ‘Central Italy’L. Spagnolo Exploratory Computing 21 / 39
    • The proposed model | Difference metrics (3)Difference bar chart • showing frequency differences for periods and civilizations associated to archaeological venues • previous query: location : ‘Southern Italy’ or ‘Insular Italy’ • current query: location : ‘Central Italy’L. Spagnolo Exploratory Computing 22 / 39
    • Outline Information exploration The proposed model The interface Conclusions PublicationsL. Spagnolo Exploratory Computing 23 / 39
    • The interface | Main elements (1) • Facet widgets Represent a specific faceting property ( mono-dimensional) Allow to apply restrictions over property values (one or more query transformations are implemented) Show the distribution of property values (according to one ore more relevance metrics) Possible visualizations depend on: type of property (functional vs. multivalued) and communicative vs. analytical purposes • Canvases Provide preview and access to information items Possibly provide aggregate view according to two or more facet properties (multidimensional) at a given level of granularity • (Interactive) query representation Shows the current selection of filters (can be embedded in facet widgets) Allows for focus change in semantic faceted explorationL. Spagnolo Exploratory Computing 24 / 39
    • The interface | Main elements (2) Demo: PoliculturaPortal www.policulturaportal.it: allows exploring 600+ interactive narratives produced within the Policultura context for schools.L. Spagnolo Exploratory Computing 25 / 39
    • The interface | Canvases (1) Mosaic canvas for PoliculturaPortal: shapes represent a fixed dimension (school level), colours a second selectable property (e.g. year)L. Spagnolo Exploratory Computing 26 / 39
    • The interface | Canvases (2) Mosaic canvas for PoliculturaPortal: items that are no more relevant for the current query disappear.L. Spagnolo Exploratory Computing 27 / 39
    • The interface | Canvases (3) Pie-chart map for PoliculturaPortal: a selected property (e.g. year) is show at different geographic levels of granularity (Region, Province)L. Spagnolo Exploratory Computing 28 / 39
    • The interface | Canvases (4) Pie-chart map for PoliculturaPortal: index providing access to items in specific selected areaL. Spagnolo Exploratory Computing 29 / 39
    • The interface | Semantic exploration (1) Concept of semantic faceted exploration for artworks. ArtExplorer Start a new exploration Exploration history Saved explorations Your exploration a painting period: XIX Century or XX Century 220 items of type Artwork matching the query author: gender: female A Canvas: Thumbnails 12345 C Main item features: location: artist: B Art Institute, Chicago 18 Berthe Morisot 21 Metropolitan, New York 39 Elizabeth Thompson 14 Musée dOrsay, Paris 40 Frida Kahlo 18 National Museum of Mary Cassatt 45 Women in the Arts, 28 Tamara de Lempicka 23 Washington D.C. Others (show) 99 Tate Gallery, London 23 Others (show) 72 art movement: Art Decò 26 subject: Impressionism 87 Preraphaelites 21 a child a drawing room a flower Realism 16 a garden a girl a landscape Surrealism 26 a person a portrait Others (show) 46 a self-portrait a theatre a woman period: technique: Charcoal 7 Oil on canvas 132 Pastels 33 1801 Show by: Decade 1992 Print 16 Watercolours 27 Others (show) 5L. Spagnolo Exploratory Computing 30 / 39
    • The interface | Semantic exploration (2) Concept of semantic faceted exploration for artworks. ArtExplorer Start a new exploration Exploration history Saved explorations Your exploration a painting period: XIX Century or XX Century 220 items of type Artwork matching the query author: gender: female A Canvas: Thumbnails 12345 C Main item features: location: artist: B Art Institute, Chicago 18 Berthe Morisot 21 Metropolitan, New York 39 Elizabeth Thompson 14 Musée dOrsay, Paris 40 Frida Kahlo 18 National Museum of Mary Cassatt 45 Women in the Arts, 28 Tamara de Lempicka 23 A Washington D.C. Others (show) 99 Tate Gallery, London 23 Others (show) 72 art movement: Query subject: a child a drawing room a flower Art Decò Impressionism Preraphaelites Realism 26 87 21 16 a garden a girl a landscape 26 representation a person a woman a portrait a self-portrait a theatre Surrealism Others (show) 46 period: a painting and technique: Charcoal 7 Oil on canvas 132 period : [‘XIX century’ or Pastels Print 33 16 1801 Show by: Decade 1992 Watercolours 27 Others (show) 5 ‘XX century’] and artist : [gender : “female”]L. Spagnolo Exploratory Computing 30 / 39
    • The interface | Semantic exploration (3) Concept of semantic faceted exploration for artworks. ArtExplorer Start a new exploration Exploration history Saved explorations Your exploration a painting period: XIX Century or XX Century 220 items of type Artwork matching the query author: gender: female A Canvas: Thumbnails 12345 C Main item features: location: artist: B Art Institute, Chicago 18 Berthe Morisot 21 Metropolitan, New York 39 Elizabeth Thompson 14 Musée dOrsay, Paris 40 Frida Kahlo 18 National Museum of Women in the Arts, Washington D.C. 28 Mary Cassatt Tamara de Lempicka Others (show) 45 23 99 B Tate Gallery, London 23 Others (show) 72 art movement: Art Decò 26 Facets widgets subject: Impressionism 87 a child a drawing room a flower a garden a girl a landscape Preraphaelites Realism Surrealism 21 16 26 • for the current a person a portrait Others (show) 46 a self-portrait a theatre a woman (main) focus period: technique: Charcoal 7 • properties of Oil on canvas 132 Pastels Print Watercolours 27 33 16 1801 Show by: Decade 1992 paintings (location, Others (show) 5 subject, artist name, technique, etc.)L. Spagnolo Exploratory Computing 30 / 39
    • The interface | Semantic exploration (4) Concept of semantic faceted exploration for artworks. ArtExplorer Start a new exploration Exploration history Saved explorations Your exploration a painting period: XIX Century or XX Century 220 items of type Artwork matching the query author: gender: female A Canvas: Thumbnails 12345 C Main item features: location: artist: B Art Institute, Chicago 18 Berthe Morisot 21 Metropolitan, New York 39 Elizabeth Thompson 14 Musée dOrsay, Paris 40 Frida Kahlo 18 National Museum of Mary Cassatt 45 Women in the Arts, 28 Tamara de Lempicka 23 Washington D.C. Others (show) 99 Tate Gallery, London 23 Others (show) 72 art movement: Art Decò 26 subject: Impressionism 87 Preraphaelites 21 a child a drawing room a flower Realism 16 a garden a girl a landscape a person a portrait a self-portrait a theatre a woman Surrealism Others (show) 26 46 C technique: Charcoal 7 period: Canvas Oil on canvas 132 Pastels Print Watercolours 27 33 16 1801 Show by: Decade 1992 • Simple thumbnail Others (show) 5 view of artworks matching the queryL. Spagnolo Exploratory Computing 30 / 39
    • The interface | Semantic exploration (5) Concept of semantic faceted exploration for artworks (other focus). ArtExplorer Start a new exploration Exploration history Saved explorations Your exploration a painting period: XIX Century or XX Century 220 items of type Artwork matching the query author: gender: female A Canvas: Thumbnails 12345 Features for this focus (58 items of type Artist ): D type: an Illustrator 8 Berthe Morisot 21 a Painter 202 Elizabeth Siddal 11 a Photographer 10 Elizabeth Thompson 14 a Sculptor 38 Evelyn De Morgan 12 Frida Kahlo 18 Georgia OKeeffe 9 Gwen John 8 art movement: Louise Bourgeois 12 Art Decò 26 Mary Cassatt 45 Impressionism 87 Natalia Goncharova 5 Suzanne Valadon 6 B Preraphaelites Realism 21 16 Tamara de Lempicka 23 Surrealism 26 Others (show) 36 Others (show) 46 country: France 47 birth: year: Mexico 18 Poland 23 United Kingdom 59 United States 62 1771 Show by: Decade 1968 Others (show) 11 C death: year: subject of a Painting 15 a Photography 3 a Drawing 1 1836 Show by: Decade aliveL. Spagnolo Exploratory Computing 31 / 39
    • The interface | Semantic exploration (6) Concept of semantic faceted exploration for artworks (other focus). ArtExplorer Start a new exploration Exploration history Saved explorations Your exploration a painting period: XIX Century or XX Century 220 items of type Artwork matching the query author: gender: female A Canvas: Thumbnails 12345 Features for this focus (58 items of type Artist ): D type: an Illustrator 8 Berthe Morisot 21 a Painter 202 Elizabeth Siddal 11 a Photographer 10 Elizabeth Thompson 14 a Sculptor 38 Frida Kahlo A Evelyn De Morgan 12 Georgia OKeeffe Gwen John 18 9 8 art movement: Louise Bourgeois 12 Art Decò 26 Mary Cassatt Query B Suzanne Valadon 45 Natalia Goncharova 5 6 Tamara de Lempicka 23 Impressionism Preraphaelites Realism Surrealism 87 21 16 26 Others (show) representation country: 36 Others (show) 46 France 47 birth: year: a painting and Mexico Poland 18 23 United Kingdom 59 United States 62 1771 Show by: Decade 1968 period : [‘XIX century’ or Others (show) C 11 death: year: ‘XX century’] and subject of a Painting 15 a Photography 3 a Drawing 1 1836 Show by: Decade alive artist : [gender : “female”]L. Spagnolo Exploratory Computing 31 / 39
    • The interface | Semantic exploration (7) Concept of semantic faceted exploration for artworks (other focus). ArtExplorer Start a new exploration Exploration history Saved explorations Your exploration a painting period: XIX Century or XX Century 220 items of type Artwork matching the query author: gender: female A Canvas: Thumbnails 12345 Features for this focus (58 items of type Artist ): B and C D type: Berthe Morisot Elizabeth Siddal 21 11 an Illustrator a Painter 8 202 a Photographer 10 Facets widgets Elizabeth Thompson 14 a Sculptor 38 Evelyn De Morgan 12 Frida Kahlo Georgia OKeeffe 18 9 • for the current focus Gwen John 8 art movement: Louise Bourgeois Mary Cassatt 12 45 Art Decò Impressionism 26 87 [gender : “female”] Natalia Goncharova 5 Suzanne Valadon 6 B Preraphaelites Realism 21 16 Tamara de Lempicka 23 Others (show) 36 Surrealism Others (show) 26 46 • list of artists names country: France 47 birth: year: (B), plus Mexico 18 Poland United Kingdom United States 23 59 62 1771 Show by: Decade 1968 • properties of artists Others (show) 11 C (C): country, type, death: year: subject of a Painting a Photography 15 3 date of birth/death, a Drawing 1 1836 Show by: Decade alive etc.L. Spagnolo Exploratory Computing 31 / 39
    • The interface | Semantic exploration (8) Concept of semantic faceted exploration for artworks (other focus). ArtExplorer Start a new exploration Exploration history Saved explorations Your exploration a painting period: XIX Century or XX Century 220 items of type Artwork matching the query author: gender: female A Canvas: Thumbnails 12345 Features for this focus (58 items of type Artist ): D type: an Illustrator 8 Berthe Morisot 21 a Painter 202 Elizabeth Siddal 11 a Photographer 10 Elizabeth Thompson 14 a Sculptor 38 Evelyn De Morgan 12 Frida Kahlo 18 Georgia OKeeffe 9 Gwen John Louise Bourgeois Mary Cassatt 8 12 45 art movement: Art Decò Impressionism 26 87 D Natalia Goncharova 5 Suzanne Valadon B Preraphaelites 21 Others (show) 6 Tamara de Lempicka 23 36 Realism Surrealism Others (show) 16 26 46 Canvas country: France Mexico 47 18 birth: year: • Simple thumbnail Poland United Kingdom United States 23 59 62 1771 Show by: Decade 1968 view of artworks Others (show) 11 C matching the query, death: year: subject of a Painting 15 the same as a Photography 3 a Drawing 1 1836 Show by: Decade alive previous oneL. Spagnolo Exploratory Computing 31 / 39
    • Outline Information exploration The proposed model The interface Conclusions PublicationsL. Spagnolo Exploratory Computing 32 / 39
    • Conclusions | Possible applications (1) • Support to knowledge acquisition and exploratory storytelling “Learning by doing” to acquire knowledge about a specific domain and its ontology → cultural heritage, edutainment Faceted exploratory applications help users focusing on the whole picture → perceive the forest rather that the trees only Exploratory storytelling: telling sorties with data, to inform and persuade → e-journalism, e-commerce, education, advertising • Exploratory analysis and user-driven feature mining Investigating underlying phenomena in the information space (correlations between features) → Support to scholar research, data warehousing (OLAP) Discovery arises from guided “trial-and-error” browsing, no need to have a preliminary hypothesis Support to decision makingL. Spagnolo Exploratory Computing 33 / 39
    • Conclusions | Possible applications (2) • Enhanced information architectures and exploratory search Enhancing findability is not the primary goal of Felis (rather aimed at supporting the other fundamental requirements of exploration) Creating complex, semantic and full boolean queries by navigation can however also serve for enhancing the retrieval of specific itemsL. Spagnolo Exploratory Computing 34 / 39
    • Conclusions | Results achieved • A general framework of design and implementation strategies for exploratory user experiences, • User-centred design methodologies have be applied on a number case studies Prototype for the Directorate-General of Antiquities, Italian Ministry of Culture PoliculturaPortal (exploring PoliCultura interactive narratives) “Twinned” applications: L4All Portal (teaching exoeriences) and University of Lugano research projects portal • JavaScript APIs allowing for fast prototyping of applications (both client-side only and based on Solr as search server) Towards computer-aided tools for design and protyping (future work) • Concepts for advanced semantic faceted exploration Future work: obtaining a prototype based on Sewelis (University of Rennes 1) as search serverL. Spagnolo Exploratory Computing 35 / 39
    • Outline Information exploration The proposed model The interface Conclusions PublicationsL. Spagnolo Exploratory Computing 36 / 39
    • Publications | So far I Journals Spagnolo, Luigi, Davide Bolchini, Paolo Paolini, and Nicoletta Di Blas (2010). “Beyond Findability: Search-Enhanced Information Architecture for Content-Intensive Rich Internet Applications”. In: Journal of Information Architecture 2.1, pp. 19–36. Conference proceedings Di Blas, N., P. Paolini, and L. Spagnolo (2012). “PoliCultura Portal: 17,000 Students Tell their Stories about Cultural Heritage”. In: Museums and the Web 2012. De Caro, Stefano, Nicoletta Di Blas, and Luigi Spagnolo (2010). “In SEARCH of Novel Ways to Design Large Cultural Heritage Websites”. In: Museum and the Web 2010 Proceedings. Ed. by J Trant and D Bearman. Archives and Museum Informatics, Toronto.L. Spagnolo Exploratory Computing 37 / 39
    • Publications | So far II De Caro, Stefano, Nicoletta Di Blas, Paolo Paolini, and Luigi Spagnolo (2009). “Search-enhanced web information architecture for findability and discovery of archeological heritage: the MiBAC-DGA case study”. In: Congresso Nazionale AICA.L. Spagnolo Exploratory Computing 38 / 39
    • Publications | In progress • L.Spagnolo , P. Paolini, and F. Ferré “Exploratory computing: a new paradigm for accessing large bodies of information” ACM Trans. on Information Systems • L.Spagnolo and S. Ferré “A flexible, user-centric language for supporting faceted explorations” IEEE Trans. On Knowledge and Data Engineering • L.Spagnolo and P. Paolini “Advanced widgets for faceted visual exploration” ACM Trans. On Computer-Human InteractionL. Spagnolo Exploratory Computing 39 / 39