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Christos Katsanos | [email protected] Tselios | [email protected] Avouris | [email protected]
AutoCardSorter: Designing the Information Architecture of a Web Site Using Latent Semantic Analysis
ACM SIGCHI | Florence, Italy | 5-10 April, 2008
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Purpose & Motivation
Automate Structural Design of Information Spaces Increase efficiency and flexibility for practitioners
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Why it is important?
Structural design greatly affects user experience
Current approaches (e.g. Card Sorting) often neglected: Time constraints Cost to recruit users and run the studies Increased complexity for data analysis Challenging for large sites (>100 pages)
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Our tool-based Methodology
Page Text Descriptions
Semantic Similarity Measure (e.g. LSA)
Hierarchical Clustering Algorithms
Interactive Tree Structure
Additional Support1. Number of Groups2. Cross-Hierarchy Links
Semantic Similarity Matrix
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The tool Interface: AutoCardSorter
Page Descriptions
Analysis Options:- Semantic Similarity Measure- Clustering Algorithm Type
Interactive Dendrogram
Validation Study Design
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Validation Study Design
vs
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Card SortingAutoCardSorter
Investigate quality of results & efficiency Health & Nutrition Site Same content item descriptions 18 representative users
Measures & Analysis
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P1 P2 P3 P4 P5
P1 -
P2 0.94 -
P3 0.11 0.33 -
P4 0.33 0.28 0.11 -
P5 0.50 0.83 0.06 0.06 -
P1 P2 P3 P4 P5
P1 -
P2 0.62 -
P3 0.21 0.14 -
P4 0.49 0.51 0.83 -
P5 0.61 0.11 0.21 0.92 -
ValiditySimilarity-Matrices Correlation
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AutoCardSorter Card Sorting
LSA (P5,P1)Frequency Users placed in Same Pile P1 and P5
Validity % Agreement of Design
1) Hierarchical Cluster Analysis of Card Sorting Data
2) AutoCardSorter vs User-Data Dendrograma) Eigenvalue Analysis to ‘cut’ objectively
b) User structure => Ideal
c) In Agreement => Longer sequence of pages grouped together in the same category as Ideal
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EfficiencyTotal Time Required
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AutoCardSorter
Card Sorting
Study Results
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Study Results - Validity
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AutoCardSorter produced results of comparative quality with Card Sorting:
Similarity-Matrices Correlation = 0.80 (P<0.01)
% Agreement of Design = 100%
AutoCardSorter Card Sorting
Study Results - Efficiency
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Discussion - Advantages
Increased efficiency (x27)
Reduces resources required
Explore alternative solutions early
Simple to learn and apply
Easy to apply for large sites (>100)
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Possibility for wider adoption
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Discussion – Current Limitations
Lack of qualitative feedback
No insight to category-labels
Future Research
More validation studies in different domains
Additional constraints (e.g. group size)
Improvements to algorithm
Dynamic semantic similarity algos (e.g. LSA IR)
Alternatives to Hierarchical Clustering (e.g.
Factor Analysis)
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A Demo - Sit back and enjoy
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Summary & Questions
Proposed an approach that automates structural design of an information space.
Validation study depicted substantial effectiveness gain, with similar results to a user-based technique
Cheap + Fast + Easy = Possibility for wider adoption
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Complementary to user-based methods
Christos Katsanos | [email protected]
Extra Slides
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More Validation StudiesDetails
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Health & Nutrition
Educational Portal
Travel & Tourism Site
# of Participants in Card Sorting 18 26 34
# of Items to Sort 16 27 38
More Validation StudiesSummary of Results
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Health & Nutrition
Educational Portal
Travel & Tourism Site
Similarity-Matrices r (p<0.01) 0.80 0.52 0.59
% Agreement of Design 100% 93% 87%
Efficiency (X Times Faster) 27 11 14
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More Validation StudiesEfficiency
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More Validation StudiesNumber of Proposed Categories
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More Validation StudiesAvg. Items/Proposed Category
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More Validation StudiesCorrelation against No of items
Statistical Semantic Similarity Measures - Overview
LSA: Latent Semantic Analysis (Landauer & Dumais, 1997) LSA-IR (Falconer et al, 2006) PLSA (Hofmann, 1999)
PMI: Point-wise Mutual Information (Manning & Schutze, 1999) PMI-IR (Turney, 2001) GLSA (Matveeva et al, 2005)
HAL: Hyperspace Analogue to Language (Lund & Burgess, 1996) COALS (Rhode et al, 2004)
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Latent Semantic Analysis
Similar documents tend to have common words
1) Parse corpora representing users’ understanding skills
2) Calculate each word’s frequency of occurrence (TDM)
3) Weight by word’s importance (document, domain)
4) Apply Singular Value Decomposition
5) LSA Index = Cos(Angle of Document Vectors) => [-1,1]
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Card SortingTypical Effort in person days
http://www.intranetleadership.com.au
Complementary to user-based methods => What’s the point?
Far better than doing nothing
User-based applied in a more focused & formative manner
Get insight before running a study
Fast redesigns30
Why 2 validation measures?
Similarity-matrices Correlation strictest approach (compares
measurements of semantic similarity) more general (does not presuppose
cluster analysis)
% Agreement of Design Less strict How close the ‘proposed’ designs are?
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