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Margareta Ackerman Clustering
Margareta Ackerman !
Clustering
Clustering is one of the most widely used tools for exploratory data analysis.
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Its purpose is to identify similar groups of item in data.
What is clustering?
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Marketing: identifying target market (similar customers) Facility allocation: Placing hospitals in a new city
Personalization: Identifying music you would like based on similar users Astronomy: Grouping starts based on their physical proximity
And much, much more! !
Clustering is applied virtually anywhere we find data.
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Applications
Imagine points in Euclidean space. !
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How would you divide them into k groups of similar items?
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Come up with your own algorithm!
Clustering algorithms: A few classical examples
How can we partition data into k groups? !
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Clustering algorithms: A few classical examples
How can we partition data into k groups? !
• Use Kruskal’s algorithm for MST (Single-linkage)
• Find the minimum cut (motivates spectral clustering methods)
• Find k “centers” that minimize the average distance to a center (k-median, k-means, ...)
• Many more... !
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Clustering algorithms often have very different input-output behavior
The “right solution" depends on the clustering application
This makes clustering inherently ambiguous.
What will you gain from the clustering course?
• Explore the landscape of clustering algorithms.
• Study “The user’s dilemma,” which is the problem of selecting clustering algorithms for specific applications.
• Become an EXPERT in applying clustering in practice.
• Learn new research on how humans cluster.
• Tackle open problems in cluster theory and practice. !
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COMPUTATIONAL CREATIVITY
Computational creativity: Arthttp://www.aaronshome.com/aaron/gallery/index.html
Computational creativity: Arthttp://www.aaronshome.com/aaron/gallery/index.html
Computational creativity: Arthttp://www.aaronshome.com/aaron/gallery/index.html
The Painting Foolhttp://www.thepaintingfool.com/
Hello there. I’m The Painting Fool. I’m a computer program that aspires
to be taken seriously as a creative artist in my own right - one day. I’ve
been programmed and trained by my teacher, Dr. Simon Colton, who is a senior lecturer here in the
Department of Computing. You can discover more about me at this website:
www.thepaintingfool.com
Generative Music• https://aeigenfeldt.wordpress.com/
research/
Computational creativity: Food
• Cognitive cooking
• Cocktails
Creativity vs creativity• Small “c” creativity: Helping us be creative
• Casual creators (http://www.galaxykate.com/)
• To a lesser degree, all the systems discussed above
Creativity vs creativity• What is creativity?
• Can computers be creative?
• Can they surprise us?
• Can they be more creative than us?
Spring 2016: Computational creativity
• Get an overview of the field
• Create a casual creator
• Do a project on a topic of your choice
• If you are interested in taking this class, let me know soon!
