Early Rumour Detection

2019, ACL data: TWITTER, WEIBO links: https://www.aclweb.org/anthology/N19-1163, https://github.com/DeepBrainAI/ERD task: Rumour Detection 这篇文章采用GRU编码社交媒体posts stream,作为环境的状态表示;训练一个分类器以GRU的状态输出为输入,对文本做二分类判断是否是rumor。用DQN训练agent,根据状态做出是否启动rumor分类器进行判断,并根据分类结果对错给予奖惩。目标就是尽可能准尽可能早地预测出社交媒体posts是否是rumor。 Focuses on the task of rumour detection; particularly, we are in- terested in understanding how early we can detect them. Our model treats social media posts (e.g. tweets) as a data stream and integrates reinforcement learning to learn the number minimum num- ber of posts required before we classify an event as a rumour. Let $E$ denote an event, and it consists of a series of relevant posts $x_i$, where $x_0$ denotes the source message and $x_T$ the last relevant message....

2021-05-01 · 3 min · Cong Chan

Matching the Blanks - Distributional Similarity for Relation Learning

2019, ACL data: KBP37, SemEval 2010 Task 8, TACRED task: Entity and Relation Extraction Build task agnostic relation representations solely from entity-linked text. 缺陷 文章认为网页中, 相同的的实体对一般指代相同的实体关系, 把实体不同的构建为负样本. 这个在单份文件中可能大概率是对的. 但是实体不完全一直不代表这个两对实体的关系不同. 所以这个作为负样本是本质上映射的是实体识别而不是关系. 比较好的方式是把实体不同但是关系一样的也考虑进来. 方法 Define Relation Statement We define a relation statement to be a block of text containing two marked entities. From this, we create training data that contains relation statements in which the entities have been replaced with a special [BLANK]...

2021-04-21 · 3 min · Cong Chan

Open-Domain Targeted Sentiment Analysis via Span-Based Extraction and Classification

2019, ACL data: SemEval 2014, SemEval 2014 ABSA, SemEval 2015, SemEval 2016 task: ABSA propose a span-based extract-then-classify framework, where multiple opinion targets are directly extracted from the sentence under the supervision of target span boundaries, and corresponding polarities are then classified using their span representations. 优点: 用指针网络选取target,避免了序列标注的搜索空间过大问题 用span边界+极性的标注方式,解决多极性的target问题 方法 Input: sentence x =(x1,..., xn) with length n, Target list T = {t1,..., tm}: each target ti is annotated with its start, end position, and its sentiment polarity...

2020-01-24 · 2 min · Cong Chan