tensorflow - 为什么我的混淆矩阵 "shifted"在右边？

Question

我基于 ResNet 50 构建了 4 种花类型的分类器。训练时准确率非常高，一切看起来都很好。然而，一旦我绘制了混淆矩阵，我发现这些值被“移动”到右侧，而不是在主对角线上。

这是什么意思？是我的数据集有问题，还是我的代码有问题？

这是我使用 ResNet 50 所做的事情:

def create_model(input_shape, top='flatten'):
    if top not in ('flatten', 'avg', 'max'):
        raise ValueError('unexpected top layer type: %s' % top)

    # connects base model with new "head"
    BottleneckLayer = {
        'flatten': Flatten(),
        'avg': GlobalAvgPooling2D(),
        'max': GlobalMaxPooling2D()
    }[top]

    base = InceptionResNetV2(input_shape=input_shape,
                             include_top=False, 
                             weights='imagenet')

    x = BottleneckLayer(base.output)
    x = Dense(NUM_OF_FLOWERS, activation='linear')(x)
    model = Model(inputs=base.inputs, outputs=x)
    return model

    base = ResNet50(input_shape=input_shape, include_top=False)
    x = Flatten()(base.output)
    x = Dense(NUM_OF_FLOWERS, activation='softmax')(x)
    model = Model(inputs=base.inputs, outputs=x)

混淆矩阵生成:

# Predict the values from the validation dataset
Y_pred = model.predict_generator(validation_generator, nb_validation_samples // batch_size+1)
# Convert predictions classes to one hot vectors 
Y_pred_classes = numpy.argmax(Y_pred, axis = 1) 
# Convert validation observations to one hot vectors
Y_true = validation_generator.classes 
# compute the confusion matrix
confusion_mtx = confusion_matrix(Y_true, Y_pred_classes) 
# plot the confusion matrix
plot_confusion_matrix(confusion_mtx, classes = range(4))

根据要求，这就是我创建生成器的方式:

train_generator = train_datagen.flow_from_directory(
    train_data_dir,
    target_size=(img_width, img_height),
    batch_size=batch_size,
    color_mode='rgb',
    class_mode='categorical',
    shuffle=True)

validation_generator = test_datagen.flow_from_directory(
    validation_data_dir,
    target_size=(img_width, img_height),
    batch_size=batch_size,
    color_mode='rgb',
    class_mode='categorical',
    shuffle=False)

这是我的混淆矩阵的相册。每次我执行 model.predict() 时，预测都会发生变化，总是将一个单元格向右移动。

Confusion Matrix Album

Answer 1

是的，我想这是代码，请检查您创建混淆矩阵的索引，它会偏离一个