Advertisements

Data Science Fundamentals: Clustering

Like Business Intelligence, the essential purpose of Data Science is to gain knowledge and insights from data. This knowledge can then be used for a variety of purposes – such as, driving more sales, retaining more employees, reducing marketing costs, and saving lives.

This is a continuation of a series of Data Science Fundamentals posts that I will be doing over the next few weeks.  In this post, I will be covering Clustering and will include an example to make it more meaningful.  A previous post covered Classification. Upcoming posts over the next few days will cover Regression, Matching, and other data science fundamental concepts.

Clustering is similar to Classification, in that, they are both used to categorize and segment data.  But Clustering is different from Classification, in that, clustering segments the data into groups (clusters) not previously defined or even known in some cases.  Clustering explores the data and finds natural groupings/clusters/classes without any targets (previously defined classes).  This is called “unsupervised” segmentation.  It clusters the data entities based on some similarity that makes them more like each other than entities in other clusters.  Therefore, this is a great first step if information about the data set is unknown.

clustering_with_outlier

Clustering: 3 clusters formed (with an outlier)

The Clustering process may yield clusters/groups than can be later used for Classification. Using the defined classes as targets is called “supervised” segmentation.  In the diagram to the right, there are 3 clusters that have been formed (red pluses, blue circles, green diamonds).

 

After a Clustering process is completed, there may be some data entities that are clustered by themselves.  In other words, they do not fall into any of the other clusters containing multiple entities.  These are classified as outliers.  An example of this can be seen in the diagram where there is an outlier in the top-left corner (purple square).  Analysis on these outliers can sometimes yield additional insight.

Software such as R and Python provides functions for performing cluster analysis/segmentation on datasets.  Future posts will cover these topics along with more details on Clustering.

Advertisements

One Response to Data Science Fundamentals: Clustering

  1. Pingback: Data Science Fundamentals: Matching | Business Intelligence - technology, solutions, and resources

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: