Data Mining - Similarity
1 - About
Simliarity = closest distance ?
You can find similarities by looking at:
- the metadata:
- Were they created at roughly the same time?
- Do they tend to get the same ratings?
- user behavior (browsing, playing, searching)
What’s similar depends on who you’re talking about. Take director Pedro Almodóvar. You might have four very different movies by Almodóvar. But he’s such a strong voice that, by himself, he makes those videos similar to one another. For a different director—say, Spielberg—that might not be the case.
Similarity is symmetric.
2 - Articles Related
3 - Function
- Regular (“Euclidean”) distance? (sum of squares of differences). Regular Euclidean distance: normally the square root but as we compare only two instances we don't need to take the square root
- Manhattan (“city‐block”) distance? (sum of absolute differences)
- Nominal attributes? Distance = 1 if different, 0 if same
- Data Mining - Cosine Similarity (Measure of Angle) String similarity Product of vector by the cosinus