We provide additional material for each method to ease the understanding and to improve your learning experience.

Cluster analysis

Example | Agriculture
Which plants show a similar growth behavior and should therefore be cultured in a similar manner?
Example | Biology
Are there unexplored genetic relationships between certain animal species?
Example | Business
Which creditworthiness levels can be distinguished based on the payment behavior of bank customers?
Example | Medicine
How can patients be divided into different groups on the basis of laboratory values in order to develop more tailored therapies?

Cluster analysis is used to bundle objects (subjects). The aim is to combine objects to different groups (i.e., clusters) in such a way that all objects in one group are as similar to each other as possible, while the groups are as dissimilar to each other as possible.

Typical examples of research questions tackled with cluster analysis are the definition of personality types based on psychographic characteristics or the definition of market segments based on demand-relevant consumer characteristics. With a subsequent discriminant analysis, we can check to what extent the variables that were used for clustering contribute to or explain the differences between the identified clusters.