Machine Learning

Question 1

types of unsupervised learning

Answer 1

density estimation
- clustering
- dimentionality reduction
blind signal separation
factor analysis
gaussians (fit from data)

Question 2

types of unsupervised learning

Answer 2

density estimation
- clustering
- dimentionality reduction
blind signal separation
factor analysis

Question 3

techniques for clustering

Answer 3

k-means

expectation maximation

Question 4

problems with k-mean

Answer 4

• need to know k
• local minimum (but the general problem is NP-hard)
• high dimensionality
• lack of mathematical basis

Question 5

problems with k-means

Answer 5

• need to know k
• local minimum (but the general problem is NP-hard)
• high dimensionality
• lack of mathematical basis

Question 6

techniques for clustering

Answer 6

k-means

expectation maximization

Question 7

problems with k-means

Answer 7

• need to know k
• local minimum (but the general problem is NP-hard)
• high dimensionality
• lack of mathematical basis

Question 8

maximum likehood estimator

Answer 8

…

Question 9

expectation maximization vs. k-means

Answer 9

soft vs. hard correspondance

Question 10

maximum likehood estimator

Answer 10

Finding particular parametric values that make the observed results the most probable (given the model)