我有线性回归模型似乎工作正常,但我想显示模型的准确性。
首先,我初始化变量和占位符......
X_train, X_test, Y_train, Y_test = train_test_split(
X_data,
Y_data,
test_size=0.2
)
n_rows = X_train.shape[0]
X = tf.placeholder(tf.float32, [None, 89])
Y = tf.placeholder(tf.float32, [None, 1])
W_shape = tf.TensorShape([89, 1])
b_shape = tf.TensorShape([1])
W = tf.Variable(tf.random_normal(W_shape))
b = tf.Variable(tf.random_normal(b_shape))
pred = tf.add(tf.matmul(X, W), b)
cost = tf.reduce_sum(tf.pow(pred-Y, 2)/(2*n_rows-1))
optimizer = tf.train.GradientDescentOptimizer(FLAGS.learning_rate).minimize(cost)
X_train
的形状为(6702, 89)
,Y_train
的形状为(6702, 1)
。接下来我运行会话,我显示每个时期的成本以及总MSE ......
init = tf.global_variables_initializer()
with tf.Session() as sess:
sess.run(init)
for epoch in range(FLAGS.training_epochs):
avg_cost = 0
for (x, y) in zip(X_train, Y_train):
x = np.reshape(x, (1, 89))
y = np.reshape(y, (1,1))
sess.run(optimizer, feed_dict={X:x, Y:y})
# display logs per epoch step
if (epoch + 1) % FLAGS.display_step == 0:
c = sess.run(
cost,
feed_dict={X:X_train, Y:Y_train}
)
y_pred = sess.run(pred, feed_dict={X:X_test})
test_error = r2_score(Y_test, y_pred)
print(test_error)
print("Epoch:", '%04d' % (epoch + 1), "cost=", "{:.9f}".format(c))
print("Optimization Finished!")
pred_y = sess.run(pred, feed_dict={X:X_test})
mse = tf.reduce_mean(tf.square(pred_y - Y_test))
print("MSE: %4f" % sess.run(mse))
这一切似乎都正常。但是,现在我想看看我的模型的准确性,所以我想实现tf.metrics.accuracy
。文档说它有2个参数,labels
和predictions
。我接下来添加了以下内容......
accuracy, accuracy_op = tf.metrics.accuracy(labels=Y_test, predictions=pred)
init_local = tf.local_variables_initializer()
sess.run(init_local)
print(sess.run(accuracy))
显然我需要初始化局部变量,但是我认为我做错了,因为打印出的准确度结果是0.0
。
我到处寻找一个有效的例子,但我无法让它为我的模型工作,实现它的正确方法是什么?