Licor's Space

General Definition of Trees A tree consists of a set of nodes and a set of edges that connect pairs of nodes. A tree is either empty or consists of a root and zero or more subtrees, each of which is also a tree. # Binary Tree Illustration class Tree: def __init__(self, value): self.key = value self.left = None self.right = None Tree Traversals Preorder Visit the root node first, then recursively do a preorder traversal of the left subtree, followed by a recursive preorder traversal of the right subtree. »

Classification Metrics Classification is about predicting class labels given input data. Take binary classification for example, there’re 2 possible classes, usually positive and negative, so we can naively use accuracy to measure the performance. $$Accuracy = {n\_correct \over n\_total}$$ In this competition, you’ll distinguish dogs from cats However, in reality, the classes are not always equal. The quantities of classes may be biased, and the cost of making wrong prediction may be different (e. »

这些模型都是在ImageNet挑战赛上具有里程碑意义的卷积神经网络模型 Alex Net Paper ReLU Nonlinearity train much faster and solve vanishing gradient problem Overlapping Pooling Reducing Overfitting Data Augmentation Dropout we first rescaled the image such that the shorter side was of length 256, and »

聚类是一个把数据对象划分为多个组或多个簇的过程。同一个簇内的对象有很高的相似性，而不同簇之间的对象有很高的相异性。 方法 一般特点 划分方法 - 发现 »

决策树可以用于分类与回归 分类 classification 与回归 regression 是机器学习中两种数值预测的形式，属于监督学习 Supervised Learning 的范围。大致区别可以用下面的表格来说明 属性 分类 回归 输出 »