Unsupervised Projection Models

Unsupervised Projection Models are models that account for the distribution of the data in an unsupervised manner without the need manually acquired labels. They typically achieve this by using techniques that factorise the data covariance matrix or cluster related data-points into groups. These models generally exhibit a good retrieval effectiveness lying somewhere between the data independent and supervised models, but suffer from the considerable advantage of being computationally expensive at training time due to the matrix factorisation component.

Name	Codebook	Architecture	Optimisation
, .	Binary	Shallow	Random Hyperplanes
, .	Binary	Deep	Backpropagation
Lin Chen, Hossein Esfandiari, Thomas Fu, Vahab S. Mirrokni, 2019. Locality-sensitive Hashing For F-divergences: Mutual Information Loss And Beyond	Binary	Shallow	Hellinger approximation
, .	Binary	Shallow	Variance Balance
, .	Binary	Shallow	Matrix Factorisation
, .	Binary	Shallow	Conditional Entropy Minimisation
, .	Binary	Shallow	Custom Iterative Scheme
, .	Binary	Shallow	Alternating Optimisation
, .	Binary	Shallow	Randomised
, .	Binary	Shallow	Matrix Factorisation
, .	Binary	Shallow	Gradient Descent
, .	Binary	Shallow	Variance Balance
, .	Binary	Shallow	Matrix Factorisation
, .	Binary	Shallow	Coordinate Descent
, .	Binary	Shallow	Alternate Optimisation
, .	Binary	Shallow	Random Permutations
, .	Binary	Deep	Backpropagation
, .	Binary	Shallow	Matrix Factorisation
, .	Binary	Shallow	Alternative Maximisation
, .	Binary	Shallow	Random Hyperplanes
, .	Binary	Shallow	Augmented Lagrangian
, .	Binary	Shallow	Random Hyperplanes
, .	Binary	Shallow	Structured Perceptron
, .	Binary	Deep	Backpropagation
Kexin Rong, Clara E. Yoon, Karianne J. Bergen, Hashem Elezabi, Peter Bailis, Philip Levis, Gregory C. Beroza, 2018. Locality-sensitive Hashing For Earthquake Detection: A Case Study Of Scaling Data-driven Science	Binary	Shallow	Random Hyperplanes
, .	Binary	Deep	Backpropagation
, .	Binary	Deep	Backpropagation
, .	Binary	Shallow	Random Hyperplanes
Jingkuan Song, Hanwang Zhang, Xiangpeng Li, Lianli Gao, Meng Wang, Richang Hong, 2018. Self-supervised Video Hashing With Hierarchical Binary Auto-encoder	Binary	Deep	Backpropagation
, .	Binary	Deep	Backpropagation
, .	Binary	Shallow	Random Hyperplanes
, .	Binary	Shallow	Matrix Factorisation (PCA)
, .	Binary	Shallow	Matrix Factorisation
, .	Binary	Shallow	Iterative optimisation
, .	Binary	Shallow	Variance Balance
, .	Binary	Deep	Backpropagation
, .	Binary	Deep	Backpropagation
, .	Binary	Deep	Backpropagation
, .	Binary	Shallow	Fast Fourier Transform