# Negation and Speculation in NLP: A Survey, Corpora, Methods, and Applications
## 2 Corpora and Annotation Process
### Corpora  
#### 2.2.1 English Corpora  
This subsection explores ten English corpora that have been annotated with negation or speculation. As shown in Table 1, they cover texts extracted from various domains (biomedical, clinical, reviews, and others). BioInfer was the first biomedical corpus to have negation annotation [49]. It is collected from abstracts of biomedical scientific papers, where 1100 sentences were annotated with entities, their relationship, and dependencies. In addition, 6% of the annotated relationships include negated cases using the 'not' cue. This corpus is publicly available ([[http://mars.cs.utu.fi/BioInfer/](http://mars.cs.utu.fi/BioInfer/)]([http://mars.cs.utu.fi/BioInfer/](http://mars.cs.utu.fi/BioInfer/)) (accessed on 1 October 2021)), and was built for information extraction systems to find relations between proteins, genes, and RNAs. The Genome Information Acquisition (GENIA) corpus was originally annotated with part of speech (PoS), syntactic trees, and terms [52; 53]. In 2008, half the GENIA corpus, 1000 Medline abstracts, was annotated with negated biological events and two levels of uncertainty [21]. It consists of 9372 sentences in which 36,114 events were identified, and it is considered the first event-annotated corpus. A chief biologist and three graduates undertook the process of annotating negated, uncertain, and other event types ([[http://www.nactem.ac.uk/meta-knowledge/Annotation_Guidelines.pdf](http://www.nactem.ac.uk/meta-knowledge/Annotation_Guidelines.pdf)]([http://www.nactem.ac.uk/meta-knowledge/Annotation_Guidelines.pdf](http://www.nactem.ac.uk/meta-knowledge/Annotation_Guidelines.pdf)) (accessed on 17 September 2021)). The corpus and its annotation guidelines are publicly available under the terms of the Creative Commons Attribution 3.0 Public License ([[http://geniaproject.org/genia-corpus/event-corpus](http://geniaproject.org/genia-corpus/event-corpus)]([http://geniaproject.org/genia-corpus/event-corpus](http://geniaproject.org/genia-corpus/event-corpus)) (accessed on 17 September 2021)). BioScope is a well-known biomedical corpus of information on negating/speculative cues and their scope [14]. It consists of documents from various sources (clinical radiology reports, full biological papers from the FlyBase and BioMed Central (BMC) website, and biological paper abstracts from the GENIA corpus [52]) covering many types of texts \begin{table}
\begin{tabular}{l c c c c c c c c c} \hline \hline
**Ref.** & **Year** & **Corpus** & **Domain** & **Size** & **Neg.** & **Spec.** & **Scope** & **Event** & **Focus** & **Avail.** \\ \hline
[49] & 2007 & BioInfer & Biomedical & 1100 & \(\surd\) & & \(\surd\) & & & \(\surd\) \\
[21] & 2008 & GENIA & Biomedical & 9372 & \(\surd\) & \(\surd\) & & \(\surd\) & & \(\surd\) \\
[14] & 2008 & BioScope & Biomedical & 20,924 & \(\surd\) & \(\surd\) & \(\surd\) & & & \(\surd\) \\
[50] & 2010 & CoNLL-2010 & Biological & 40,289 & & \(\surd\) & \(\surd\) & & & \(\surd\) \\
[44] & 2010 & Product Review & Review & 2111 & \(\surd\) & & \(\surd\) & & & \\
[51] & 2011 & PropBank FOC & Journal & 3779 & \(\surd\) & & & & \(\surd\) & \(\surd\) \\
[40] & 2012 & SFU Review & Review & 17,263 & \(\surd\) & \(\surd\) & \(\surd\) & & & \(\surd\) \\
[41] & 2012 & ConanDoyle-neg & Short & 4423 & \(\surd\) & & \(\surd\) & \(\surd\) & & \(\surd\) \\
[8] & 2015 & Twitter Negation & Tweets & 4000 & \(\surd\) & & \(\surd\) & & & \\
[27] & 2016 & DT-Neg & Dialogues & 27,785 responses & \(\surd\) & & \(\surd\) & & \(\surd\) \\
[45] & 2018 & SFU SOCC & Opinion & 1043 comments & \(\surd\) & & \(\surd\) & & \(\surd\) & \(\surd\) \\ \hline \hline \end{tabular}
\end{table} 
Table 1: English corpora annotated for negation and/or speculation. in the biomedical domain. It comprises 6383 clinical texts (radiology reports), 2670 sentences from full scientific papers, and 11,871 sentences from scientific papers' abstracts. Two independent annotators annotated it, following the annotation guidelines written by a linguist expert.