
Randall G. answered 07/15/21
Physicist/Data Scientist
This is an old question, but SOM is not a supervised learning approach. But if can be used to reduce the dimensionality of your data to use for a supervised learning algorithm.
For example, SOM may be used to group long input sequences together based on features that it discovers into vectors of a much smaller size--say, using SOM to reduce 100,000 1000-length sequences to 100,000 (or fewer) 100-length sequences. These resultant vectors may then be used to train a supervised algorithm.