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import matplotlib.pyplot as plt
import numpy
from keras import callbacks
from keras import optimizers
from keras.layers import Dense
from keras.models import Sequential
from keras.callbacks import ModelCheckpoint
from sklearn.preprocessing import StandardScaler
#TensorBoard callback for visualization of training history
tb = callbacks.TensorBoard(log_dir='./logs/latest', histogram_freq=10, batch_size=32,
write_graph=True, write_grads=True, write_images=False,
embeddings_freq=0, embeddings_layer_names=None, embeddings_metadata=None)
# Early stopping - Stop training before overfitting
early_stop = callbacks.EarlyStopping(monitor='val_loss', min_delta=0, patience=3, verbose=1, mode='auto')
# fix random seed for reproducibility
seed = 42
numpy.random.seed(seed)
# load pima indians dataset
dataset = numpy.loadtxt("pima-indians-diabetes.csv", delimiter=",")
# split into input (X) and output (Y) variables
X = dataset[:, 0:8]
Y = dataset[:, 8]
# Standardize features by removing the mean and scaling to unit variance
scaler = StandardScaler()
X = scaler.fit_transform(X)
#ADAM Optimizer with learning rate decay
opt = optimizers.Adam(lr=0.0001, beta_1=0.9, beta_2=0.999, epsilon=1e-08, decay=0.0001)
## Create our model
model = Sequential()
model.add(Dense(12, input_dim=8, kernel_initializer='uniform', activation='relu'))
model.add(Dense(8, kernel_initializer='uniform', activation='relu'))
model.add(Dense(1, kernel_initializer='uniform', activation='sigmoid'))
# Compile the model using binary crossentropy since we are predicting 0/1
model.compile(loss='binary_crossentropy',
optimizer=opt,
metrics=['accuracy'])
# checkpoint
filepath="./checkpoints/weights.best.hdf5"
checkpoint = ModelCheckpoint(filepath, monitor='val_acc', verbose=1, save_best_only=True, mode='max')
# Fit the model
history = model.fit(X, Y, validation_split=0.33, epochs=10000, batch_size=10, verbose=0, callbacks=[tb,early_stop,checkpoint])
# list all data in history
print(history.history.keys())
# summarize history for accuracy
plt.plot(history.history['acc'])
plt.plot(history.history['val_acc'])
plt.title('model accuracy')
plt.ylabel('accuracy')
plt.xlabel('epoch')
plt.legend(['train', 'test'], loc='upper left')
plt.show()
# summarize history for loss
plt.plot(history.history['loss'])
plt.plot(history.history['val_loss'])
plt.title('model loss')
plt.ylabel('loss')
plt.xlabel('epoch')
plt.legend(['train', 'test'], loc='upper left')
plt.show()
を私は早く停止、チェックポイントとTensorboardコールバックを追加し、以下の結果持っている:
をEpoch 00000: val_acc improved from -inf to 0.67323, saving model to ./checkpoints/weights.best.hdf5
Epoch 00001: val_acc did not improve
...
Epoch 00024: val_acc improved from 0.67323 to 0.67323, saving model to ./checkpoints/weights.best.hdf5
...
Epoch 00036: val_acc improved from 0.76378 to 0.76378, saving model to ./checkpoints/weights.best.hdf5
...
Epoch 00044: val_acc improved from 0.79921 to 0.80709, saving model to ./checkpoints/weights.best.hdf5
...
Epoch 00050: val_acc improved from 0.80709 to 0.80709, saving model to ./checkpoints/weights.best.hdf5
...
Epoch 00053: val_acc improved from 0.80709 to 0.81102, saving model to ./checkpoints/weights.best.hdf5
...
Epoch 00257: val_acc improved from 0.81102 to 0.81102, saving model to ./checkpoints/weights.best.hdf5
...
Epoch 00297: val_acc improved from 0.81102 to 0.81496, saving model to ./checkpoints/weights.best.hdf5
Epoch 00298: val_acc did not improve
Epoch 00299: val_acc did not improve
Epoch 00300: val_acc did not improve
Epoch 00301: val_acc did not improve
Epoch 00302: val_acc did not improve
Epoch 00302: early stopping
ログによると、私のモデルの精度は0.81496です。奇妙なことは、検証精度がトレーニング精度(0.81対0.76)より高く、検証損失がトレーニング損失(0.41対0.47)よりも低いことです。
Q:は、私が何をしないのです、私はこの問題を解決するために、自分のコードに変更すること何が必要ですか?
私はそれが問題を修正するかどうかを確認するためにデータセットをシャッフルします。 –
ケラスのやり方はありますか? –
Hm、 '' model.fit'の 'shuffle'引数がTrue(デフォルト)に設定されている場合、各エポックでトレーニングデータがランダムにシャッフルされます*](https://keras.io/getting -started/faq /#は、トレーニング中にデータシャッフルされたものです)。 –