'Similarity' in Data Mining

Question

In the field of Data Mining, is there a specific sub-discipline called \'Similarity\'? If yes, what does it deal with. Any examples, links, references will be helpful.

Answer 1

Just to stress the importance of the "similarity" concept.

Data mining (AI, machine learning, modelling etc) is about bringing some function to either it's maximum or minimum value. Take the best optimization/learning/mining algorithm and a wrong function and you get a complete garbage. Note that we use "value" and not "valueS". That's because there is no (to my best knowledge) algorithm (computational or other) that is capable of optimizing more than one value. However, in our Universe, complex optimizations are more frequent than one-dimensional ones (we want to be rich AND young AND healthy). That is why there a plethora of similarity and other scoring functions exists. And that is why none of them is "the right one"