公式top-5 accuracy=
时间: 2024-03-04 22:52:08 浏览: 16
top-5 accuracy是指在分类任务中,预测的类别在前5个中包含了真实类别的样本占全部样本的比例。其公式如下:
top-5 accuracy = (至少有一个正确分类的样本数) / (总样本数)
其中,至少有一个正确分类的样本数指的是预测的类别中包含了真实类别的样本数。总样本数指的是所有样本的数量。
相关问题
Top-5 accuracy
Top-5 accuracy is a metric used to evaluate the performance of a machine learning model in a multi-class classification problem. It measures the percentage of times that the correct label appears in the top five predictions made by the model. For example, if the correct label is "dog" and the model's top five predictions are "cat", "horse", "dog", "sheep", and "cow", then the model's top-5 accuracy is 1 (or 100%) because "dog" appears in the top five predictions. Top-5 accuracy is often used in image classification tasks where there may be multiple objects present in the image and the model needs to identify all of them.
什么是top-1 accuracy
Top-1 accuracy是指在分类任务中,模型正确预测出测试集中样本的类别的概率。具体来说,对于每个测试样本,模型会输出一个预测概率分布,其中概率最高的那个类别就是模型的预测结果。如果这个预测结果与该样本的真实类别一致,则认为该样本被正确分类,Top-1 accuracy就是计算模型正确分类的样本数除以测试集总样本数的比例。