Which of the following is unsupervised machine learning?

Related questions

1. What is divisive clustering?
2. Are decision trees supervised or unsupervised?
3. What is clustering techniques in data mining?
4. Can decision trees be used for unsupervised learning?

Tags

1. #consisting
2. #labeled
3. #unsupervised
4. #method
5. #cluster
6. #hidden
7. #without
8. #inferences
9. #patterns
10. #common
11. #grouping
12. #algorithm
13. #responses
14. #analysis
15. #which
16. #datasets
17. #input
18. #learning
19. #machine
20. #exploratory