Kaggle competition: Quora Insincere Questions Classification
y = np.where(train_df['target'] >= 0.5, 1, 0 )<predict_on_test>
embed_size = 300
max_features = 95000
maxlen = 70
class NbSvmClassifier(BaseEstimator, ClassifierMixin):
def __init__(self, C=1.0, dual=False, n_jobs=1):
self.C = C
self.dual = dual
self.n_jobs = n_jobs
def predict(self, x):
check_is_fitted(self, ['_r', '_clf'])
 return self._clf.predict(x.multiply(self._r))
def predict_proba(self, x):
check_is_fitted(self, ['_r', '_clf'])
 return self._clf.predict_proba(x.multiply(self._r))
def fit(self, x, y):
y = y
x, y = check_X_y(x, y, accept_sparse=True)
 def pr(x, y_i, y):
p = x[y==y_i].sum(0)
 return(p+1)/(( y==y_i ).sum() +1)
 self._r = sparse.csr_matrix(np.log(pr(x,1,y)/ pr(x,0,y)))
 x_nb = x.multiply(self._r)
 self._clf = LogisticRegression(C=self.C, dual=self.dual, n_jobs=self.n_jobs ).fit(x_nb, y)
 return self<train_model>
import os
import time
import numpy as np
import pandas as pd
from tqdm import tqdm
import math
from sklearn.model_selection import train_test_split
from sklearn import metrics
from sklearn.model_selection import GridSearchCV, StratifiedKFold
from sklearn.metrics import f1_score, roc_auc_score
from keras.preprocessing.text import Tokenizer
from keras.preprocessing.sequence import pad_sequences
from keras.layers import Dense, Input, CuDNNLSTM, Embedding, Dropout, Activation, CuDNNGRU, Conv1D
from keras.layers import Bidirectional, GlobalMaxPool1D, GlobalMaxPooling1D, GlobalAveragePooling1D
from keras.layers import Input, Embedding, Dense, Conv2D, MaxPool2D, concatenate
from keras.layers import Reshape, Flatten, Concatenate, Dropout, SpatialDropout1D
from keras.optimizers import Adam
from keras.models import Model
from keras import backend as K
from keras.engine.topology import Layer
from keras import initializers, regularizers, constraints, optimizers, layers
from keras.layers import concatenate
NbSvm = NbSvmClassifier(C=1.5, dual=True, n_jobs=-1)
 NbSvm.fit(train, y )<predict_on_test>
def load_and_prec() :
train_df = pd.read_csv(".. /input/train.csv")
 test_df = pd.read_csv(".. /input/test.csv")
 print("Train shape : ",train_df.shape)
 print("Test shape : ",test_df.shape)
 train_X = train_df["question_text"].fillna("_
test_X = test_df["question_text"].fillna("_
tokenizer = Tokenizer(num_words=max_features)
 tokenizer.fit_on_texts(list(train_X))
train_X = tokenizer.texts_to_sequences(train_X)
 test_X = tokenizer.texts_to_sequences(test_X)
 train_X = pad_sequences(train_X, maxlen=maxlen)
 test_X = pad_sequences(test_X, maxlen=maxlen)
 train_y = train_df['target'].values
np.random.seed(2018)
 trn_idx = np.random.permutation(len(train_X))
train_X = train_X[trn_idx]
train_y = train_y[trn_idx]
return train_X, test_X, train_y, tokenizer.word_index
prediction=NbSvm.predict_proba(test)[:,1]<save_to_csv>
def load_glove(word_index):
EMBEDDING_FILE = '.. /input/embeddings/glove.840B.300d/glove.840B.300d.txt'
def get_coefs(word,*arr): return word, np.asarray(arr, dtype='float32')
 embeddings_index = dict(get_coefs(*o.split(" ")) for o in open(EMBEDDING_FILE))
all_embs = np.stack(embeddings_index.values())
 emb_mean,emb_std = all_embs.mean() , all_embs.std()
embed_size = all_embs.shape[1]
nb_words = min(max_features, len(word_index))
embedding_matrix = np.random.normal(emb_mean, emb_std,(nb_words, embed_size))
for word, i in word_index.items() :
if i >= max_features: continue
embedding_vector = embeddings_index.get(word)
 if embedding_vector is not None: embedding_matrix[i] = embedding_vector
return embedding_matrix
def load_fasttext(word_index):
EMBEDDING_FILE = '.. /input/embeddings/wiki-news-300d-1M/wiki-news-300d-1M.vec'
def get_coefs(word,*arr): return word, np.asarray(arr, dtype='float32')
 embeddings_index = dict(get_coefs(*o.split(" ")) for o in open(EMBEDDING_FILE)if len(o)>100)
 all_embs = np.stack(embeddings_index.values())
 emb_mean,emb_std = all_embs.mean() , all_embs.std()
embed_size = all_embs.shape[1]
nb_words = min(max_features, len(word_index))
embedding_matrix = np.random.normal(emb_mean, emb_std,(nb_words, embed_size))
for word, i in word_index.items() :
if i >= max_features: continue
embedding_vector = embeddings_index.get(word)
 if embedding_vector is not None: embedding_matrix[i] = embedding_vector
return embedding_matrix
def load_para(word_index):
EMBEDDING_FILE = '.. /input/embeddings/paragram_300_sl999/paragram_300_sl999.txt'
def get_coefs(word,*arr): return word, np.asarray(arr, dtype='float32')
 embeddings_index = dict(get_coefs(*o.split(" ")) for o in open(EMBEDDING_FILE, encoding="utf8", errors='ignore')if len(o)>100)
 all_embs = np.stack(embeddings_index.values())
 emb_mean,emb_std = all_embs.mean() , all_embs.std()
embed_size = all_embs.shape[1]
nb_words = min(max_features, len(word_index))
embedding_matrix = np.random.normal(emb_mean, emb_std,(nb_words, embed_size))
for word, i in word_index.items() :
if i >= max_features: continue
embedding_vector = embeddings_index.get(word)
 if embedding_vector is not None: embedding_matrix[i] = embedding_vector
return embedding_matrix
submission = pd.read_csv(".. /input/jigsaw-unintended-bias-in-toxicity-classification/sample_submission.csv")
 submission['prediction'] = 0.2*prediction + 0.3*test_pred
submission.to_csv('submission.csv', index=False )<import_modules>
class Attention(Layer):
def __init__(self, step_dim,
W_regularizer=None, b_regularizer=None,
W_constraint=None, b_constraint=None,
bias=True, **kwargs):
self.supports_masking = True
self.init = initializers.get('glorot_uniform')
 self.W_regularizer = regularizers.get(W_regularizer)
 self.b_regularizer = regularizers.get(b_regularizer)
 self.W_constraint = constraints.get(W_constraint)
 self.b_constraint = constraints.get(b_constraint)
 self.bias = bias
self.step_dim = step_dim
self.features_dim = 0
super(Attention, self ).__init__(**kwargs)
 def build(self, input_shape):
assert len(input_shape)== 3
self.W = self.add_weight(( input_shape[-1],),
initializer=self.init,
name='{}_W'.format(self.name),
regularizer=self.W_regularizer,
constraint=self.W_constraint)
 self.features_dim = input_shape[-1]
if self.bias:
self.b = self.add_weight(( input_shape[1],),
initializer='zero',
name='{}_b'.format(self.name),
regularizer=self.b_regularizer,
constraint=self.b_constraint)
 else:
self.b = None
self.built = True
def compute_mask(self, input, input_mask=None):
return None
def call(self, x, mask=None):
features_dim = self.features_dim
step_dim = self.step_dim
eij = K.reshape(K.dot(K.reshape(x,(-1, features_dim)) ,
K.reshape(self.W,(features_dim, 1))),(-1, step_dim))
if self.bias:
eij += self.b
eij = K.tanh(eij)
 a = K.exp(eij)
 if mask is not None:
a *= K.cast(mask, K.floatx())
 a /= K.cast(K.sum(a, axis=1, keepdims=True)+ K.epsilon() , K.floatx())
 a = K.expand_dims(a)
 weighted_input = x * a
return K.sum(weighted_input, axis=1)
 def compute_output_shape(self, input_shape):
return input_shape[0], self.features_dim
print(os.listdir(".. /input"))
print(os.listdir(".. /input/glove840b300dtxt"))
print(os.listdir(".. /input/fasttext-crawl-300d-2m"))
print(os.listdir(".. /input/jigsaw-unintended-bias-in-toxicity-classification")) 
<define_variables>
def model_lstm_atten(embedding_matrix):
inp = Input(shape=(maxlen,))
x = Embedding(max_features, embed_size, weights=[embedding_matrix], trainable=False )(inp)
 x = Bidirectional(CuDNNLSTM(40, return_sequences=True))(x)
 x = Bidirectional(CuDNNGRU(40, return_sequences=True))(x)
 atten = Attention(maxlen )(x)
 avg_pool = GlobalAveragePooling1D()(x)
 max_pool = GlobalMaxPooling1D()(x)
 conc = concatenate([atten, avg_pool, max_pool])
 conc = Dense(64, activation="relu" )(conc)
 conc = Dropout(0.1 )(conc)
 outp = Dense(1, activation="sigmoid" )(conc)
 model = Model(inputs=inp, outputs=outp)
 model.compile(loss='binary_crossentropy', optimizer='adam', metrics=['accuracy'])
 return model
SEED = 1234
EMBEDDING_FILES = [
'.. /input/fasttext-crawl-300d-2m/crawl-300d-2M.vec',
'.. /input/glove840b300dtxt/glove.840B.300d.txt'
]
NUM_MODELS = 8
BATCH_SIZE = 512
LSTM_UNITS = 128
DENSE_HIDDEN_UNITS = 4 * LSTM_UNITS
EPOCHS = 1
MAX_LEN = 220
DROPOUT_RATE = 0.3
IDENTITY_COLUMNS = [
'male', 'female', 'homosexual_gay_or_lesbian', 'christian', 'jewish',
'muslim', 'black', 'white', 'psychiatric_or_mental_illness'
]
AUX_COLUMNS = ['target', 'severe_toxicity', 'obscene', 'identity_attack', 'insult', 'threat']
TEXT_COLUMN = 'comment_text'
TARGET_COLUMN = 'target'
CHARS_TO_REMOVE = '""“”’`'!"
“”’'∞θ÷α•à−β∅³π‘₹´°£€\×™√²—' 
<define_variables>
def train_pred(model, train_X, train_y, val_X, val_y, epochs=2):
for e in range(epochs):
model.fit(train_X, train_y, batch_size=512, epochs=1, validation_data=(val_X, val_y))
pred_val_y = model.predict([val_X], batch_size=1024, verbose=0)
 best_thresh = 0.5
best_score = 0.0
for thresh in np.arange(0.1, 0.501, 0.01):
thresh = np.round(thresh, 2)
 score = metrics.f1_score(val_y,(pred_val_y > thresh ).astype(int))
if score > best_score:
best_thresh = thresh
best_score = score
print("Val F1 Score: {:.4f}".format(best_score))
pred_test_y = model.predict([test_X], batch_size=1024, verbose=0)
 return pred_val_y, pred_test_y, best_score
CONTRACTIONS = {"ain't": "is not", "aren't": "are not","can't": "cannot", "'cause": "because", "could've": "could have", "couldn't": "could not", "didn't": "did not",
"doesn't": "does not", "don't": "do not", "hadn't": "had not", "hasn't": "has not", "haven't": "have not", "he'd": "he would","he'll": "he will", "he's": "he is",
"how'd": "how did", "how'd'y": "how do you", "how'll": "how will", "how's": "how is", "I'd": "I would", "I'd've": "I would have", "I'll": "I will",
"I'll've": "I will have","I'm": "I am", "I've": "I have", "i'd": "i would", "i'd've": "i would have", "i'll": "i will", "i'll've": "i will have",
"i'm": "i am", "i've": "i have", "isn't": "is not", "it'd": "it would", "it'd've": "it would have", "it'll": "it will", "it'll've": "it will have",
"it's": "it is", "let's": "let us", "ma'am": "madam", "mayn't": "may not", "might've": "might have","mightn't": "might not","mightn't've": "might not have",
"must've": "must have", "mustn't": "must not", "mustn't've": "must not have", "needn't": "need not", "needn't've": "need not have","o'clock": "of the clock",
"oughtn't": "ought not", "oughtn't've": "ought not have", "shan't": "shall not", "sha'n't": "shall not", "shan't've": "shall not have", "she'd": "she would",
"she'd've": "she would have", "she'll": "she will", "she'll've": "she will have", "she's": "she is", "should've": "should have", "shouldn't": "should not",
"shouldn't've": "should not have", "so've": "so have","so's": "so as", "this's": "this is","that'd": "that would", "that'd've": "that would have",
"that's": "that is", "there'd": "there would", "there'd've": "there would have", "there's": "there is", "here's": "here is","they'd": "they would",
"they'd've": "they would have", "they'll": "they will", "they'll've": "they will have", "they're": "they are", "they've": "they have", "to've": "to have",
"wasn't": "was not", "we'd": "we would", "we'd've": "we would have", "we'll": "we will", "we'll've": "we will have", "we're": "we are", "we've": "we have",
"weren't": "were not", "what'll": "what will", "what'll've": "what will have", "what're": "what are", "what's": "what is", "what've": "what have",
"when's": "when is", "when've": "when have", "where'd": "where did", "where's": "where is", "where've": "where have", "who'll": "who will",
"who'll've": "who will have", "who's": "who is", "who've": "who have", "why's": "why is", "why've": "why have", "will've": "will have", "won't": "will not",
"won't've": "will not have", "would've": "would have", "wouldn't": "would not", "wouldn't've": "would not have", "y'all": "you all", "y'all'd": "you all would",
"y'all'd've": "you all would have","y'all're": "you all are","y'all've": "you all have","you'd": "you would", "you'd've": "you would have",
"you'll": "you will", "you'll've": "you will have", "you're": "you are", "you've": "you have", "it's": "it is" }<feature_engineering>
train_X, test_X, train_y, word_index = load_and_prec()
embedding_matrix_1 = load_glove(word_index)
 embedding_matrix_3 = load_para(word_index )
def seed_everything(seed):
random.seed(seed)
 os.environ['PYTHONHASHSEED'] = str(seed)
 np.random.seed(seed)
 def clean_contractions(str, mapping):

 specials = ["’", "‘", "´", "`"]
for s in specials:
str = str.replace(s, "'")
 res = ' '.join([mapping[t] if t in mapping else t for t in str.split(' ')])
 return res
def clean_special_chars(text, punct, replacement=' '):

 for p in punct:
text = text.replace(p, replacement)
 return text
def preprocess(data):
data = data.astype(str)
 data = data.apply(lambda x: clean_contractions(x, mapping=CONTRACTIONS))
data = data.apply(lambda x: clean_special_chars(x, punct=CHARS_TO_REMOVE))
return data
def get_coefs(word, *arr):
return word, np.asarray(arr, dtype='float32')
 def load_embeddings(path):
with open(path)as f:
return dict(get_coefs(*line.strip().split(' ')) for line in f)
 def build_matrix(word_index, path):
embedding_index = load_embeddings(path)
 embedding_matrix = np.zeros(( len(word_index)+ 1, 300))
for word, i in word_index.items() :
try:
embedding_matrix[i] = embedding_index[word]
except KeyError:
pass
return embedding_matrix
def build_model(embedding_matrix, num_aux_targets):
words = Input(shape=(None,))
x = Embedding(*embedding_matrix.shape, weights=[embedding_matrix], trainable=False )(words)
 x = SpatialDropout1D(DROPOUT_RATE )(x)
 x = Bidirectional(CuDNNLSTM(LSTM_UNITS, return_sequences=True))(x)
 x = Bidirectional(CuDNNLSTM(LSTM_UNITS, return_sequences=True))(x)
 hidden = concatenate([
GlobalMaxPooling1D()(x),
GlobalAveragePooling1D()(x),
])
 hidden = add([hidden, Dense(DENSE_HIDDEN_UNITS, activation='relu' )(hidden)])
 hidden = add([hidden, Dense(DENSE_HIDDEN_UNITS, activation='relu' )(hidden)])
 result = Dense(1, activation='sigmoid' )(hidden)
 aux_result = Dense(num_aux_targets, activation='sigmoid' )(hidden)
 model = Model(inputs=words, outputs=[result, aux_result])
 model.compile(loss='binary_crossentropy', optimizer='adam')
 return model<load_from_csv>
embedding_matrix = np.mean([embedding_matrix_1, embedding_matrix_3], axis = 0)
 np.shape(embedding_matrix )
seed_everything(SEED)
 train_df = pd.read_csv('.. /input/jigsaw-unintended-bias-in-toxicity-classification/train.csv')
 test_df = pd.read_csv('.. /input/jigsaw-unintended-bias-in-toxicity-classification/test.csv')
 train_df.shape, test_df.shape<prepare_x_and_y>
def threshold_search(y_true, y_proba):
best_threshold = 0
best_score = 0
for threshold in [i * 0.01 for i in range(100)]:
score = f1_score(y_true=y_true, y_pred=y_proba > threshold)
 if score > best_score:
best_threshold = threshold
best_score = score
search_result = {'threshold': best_threshold, 'f1': best_score}
return search_result
%%time
x_train = preprocess(train_df[TEXT_COLUMN])
 y_train = train_df[TARGET_COLUMN].values
y_aux_train = train_df[AUX_COLUMNS].values
x_test = preprocess(test_df[TEXT_COLUMN])
 for column in IDENTITY_COLUMNS + [TARGET_COLUMN]:
train_df[column] = np.where(train_df[column] >= 0.5, True, False )<define_variables>
DATA_SPLIT_SEED = 2018
train_meta = np.zeros(train_y.shape)
 test_meta = np.zeros(test_X.shape[0])
 splits = list(StratifiedKFold(n_splits=5, shuffle=True, random_state=DATA_SPLIT_SEED ).split(train_X, train_y))
for idx,(train_idx, valid_idx)in enumerate(splits):
X_train = train_X[train_idx]
y_train = train_y[train_idx]
X_val = train_X[valid_idx]
y_val = train_y[valid_idx]
model = model_lstm_atten(embedding_matrix)
 pred_val_y, pred_test_y, best_score = train_pred(model, X_train, y_train, X_val, y_val, epochs = 4)
 train_meta[valid_idx] = pred_val_y.reshape(-1)
 test_meta += pred_test_y.reshape(-1)/ len(splits )
<string_transform><EOS> 
search_result = threshold_search(train_y, train_meta)
 print(search_result)
 sub = pd.read_csv('.. /input/sample_submission.csv')
 sub.prediction = test_meta > search_result['threshold']
sub.to_csv("submission.csv", index=False )