Data and Databases

This chapter covers the concepts of data and databases. Businesses are becoming more and more "data-driven"; understanding how data is collected, stored, and managed is essential for anyone wanting to succeed in business. Pay special attention to the sections on data warehouses and data mining, as they provide examples of how companies use data strategically.

Finding Value in Data: Business Intelligence

Data Mining and Machine Learning

Data mining is the process of analyzing data to find previously unknown and interesting trends, patterns, and associations in order to make decisions. Generally, data mining is accomplished through automated means against extremely large data sets, such as a data warehouse. Some examples of data mining include:

  • An analysis of sales from a large grocery chain might determine that milk is purchased more frequently the day after it rains in cities with a population of less than 50,000.
  • A bank may find that loan applicants whose bank accounts show particular deposit and withdrawal patterns are not good credit risks.
  • A baseball team may find that collegiate baseball players with specific statistics in hitting, pitching, and fielding make for more successful major league players.

One data mining method that an organization can use to do these analyses is called machine learning. Machine learning is used to analyze data and build models without being explicitly programmed to do so. Two primary branches of machine learning exist: supervised learning and unsupervised learning.

Supervised learning occurs when an organization has data about past activity that has occurred and wants to replicate it. For example, if they want to create a new marketing campaign for a particular product line, they may look at data from past marketing campaigns to see which of their consumers responded most favorably. Once the analysis is done, a machine learning model is created that can be used to identify these new customers. It is called "supervised" learning because we are directing (supervising) the analysis towards a result (in our example: consumers who respond favorably). Supervised learning techniques include analyses such as decision trees, neural networks, classifiers, and logistic regression.

Unsupervised learning occurs when an organization has data and wants to understand the relationship(s) between different data points. For example, if a retailer wants to understand purchasing patterns of its customers, an unsupervised learning model can be developed to find out which products are most often purchased together or how to group their customers by purchase history. Is it called "unsupervised" learning because no specific outcome is expected. Unsupervised learning techniques include clustering and association rules.