Trevor Bedford (@trvrb)
27 Jun 2018
VIDD Faculty Retreat
Union, WA
480k ratings on 18k movies
28 Days Later | Contagion | Outbreak | |
Alice | 3 | ||
Bob | 1 | 4 | |
Carol | 5 | 3 |
Winning algorithm was a hand-tuned ensemble of matrix factorization, neighborhood models with temporal dynamics, restricted Boltzmann machines and gradient boosted decision trees
movie_count = 17771
user_count = 2649430
model_left = Sequential()
model_left.add(Embedding(movie_count, 60, input_length=1))
model_right = Sequential()
model_right.add(Embedding(user_count, 20, input_length=1))
model = Sequential()
model.add(Merge([model_left, model_right], mode='concat'))
model.add(Flatten())
model.add(Dense(64))
model.add(Activation('sigmoid'))
model.add(Dense(64))
model.add(Activation('sigmoid'))
model.add(Dense(64))
model.add(Activation('sigmoid'))
model.add(Dense(1))
model.compile(loss='mean_squared_error')