知识图谱复习大纲 Week 1IntroWhat is a KG?KG is the Knowledge in graph form, it captures entities, attributes, and relationships. In KG, nodes are entities and they are labeled with attributes. Edges between two nodes 2020-12-03 Knowledge Graph
知识图谱键连数据与语义网络 Web of documents vs. Web of dataWeb of Document: 数据之间关联少Analogy: a global filesystemPrimary objects: documentsLinks between: documents (or sub-parts of)Degree of structure in objects: fairly lowSemant 2020-12-03 Knowledge Graph
知识图谱图分析&问题回答 图分析图分析算法 Pathfinding and Search: Djikstra’s algorithmMatching and coloring: k-coloring, graph equivalenceCentrality: Degree centrality, page-rank, betweenness centrality, closeness centralityClusterin 2020-12-03 Knowledge Graph
知识图谱图嵌入 基础知识数据的表示Scalar: a 标量，0维Vector: a[i]， 向量，1维Matrix: a[i,j]， 矩阵，2维Tensor: a[i,j,k]， 张量，多维 Tensor和 Graph的关系:Graphs over time -> 3rd order tensors Knowledge Graphs: a directed heterogeneous multigrap 2020-12-03 Knowledge Graph
知识图谱表格理解 数据类型 Structured Data Knowledge Graphs The Semantic Web Databases Structured files (CSV, XML, XLS) Structures in HTML, e.g. tables -> 本章关注 Unstructured Data Web中的结构化表格 (Structured Tables on the 2020-12-03 Knowledge Graph
知识图谱RDFa RDFaResource Description Framework in attributes 定义:RDFa是一个W3C推荐标准。它扩展了XHTML的几个属性，网页制作者可以利用这些属性在网页中添加可供机器读取的后设资料。与RDF资料模型的对应关系使得RDFa可以将RDF的三元组嵌入在XHTML文档中，它也使得符合标准的使用端可以从RDFa文件中提取出这些RDF三元组来。 简单的说：RDF 2020-12-03 Knowledge Graph
知识图谱本体与推理 本体 Ontology从一个例子讲起12345name rankBob CaptainSue SargentMary AdmiralJoe Sargent select ?x { ?x rank “Sargent” }select ?x { ?x a Person }select ?x { ?x a MilitaryPerson } 如何进行inference?Tell th 2020-12-03 Knowledge Graph
知识图谱Blocking&关系型实体解析 实体解析回顾Deduplication: Merging Ambiguous Entities (KG->KG)Record Linkage: Combining KGs (KG1->KG2)Entity Mapping/Linking: Integrating New Candidates (text -> KG) Blocking简单匹配的问题: Comparing each 2020-12-02 Knowledge Graph
知识图谱信息提取-Snorkel Dark Data ExtractionStructured Data(4%): Data easy to process by machinesDark Data(96%): Valuable & hard to process. (占据的web信息的绝大部分)example: Scientific articles & government reports，Medical Im 2020-12-02 Knowledge Graph
知识图谱字符串匹配 字符串匹配问题Problem Statement:Given X and Y sets of strings, Find pairs (x, y) such that both x and y refer to the same real world entity. Then use precision(fraction of pairs found that are correct) and 2020-12-01 Knowledge Graph