The Pros and Cons of Using the Top 5 Open-Source Named Entity Recognition Datasets

What is Named Entity Recognition (NER)? 

Named Entity Recognition (NER) is a natural language processing (NLP) subtask that involves automatically identifying and categorizing named entities mentioned in a text, such as people, organizations, locations, dates, and other proper nouns. NER is an essential step in many NLP tasks, such as information extraction and text summarization. 

To perform NER, an NLP model first parses the text to identify words or phrases that are likely to be named entities. The model then assigns a category tag to each named entity based on its context within the text. For example, a phrase like “President Biden” would be tagged as a “Person,” while a phrase like “Mount Everest” would be tagged as a “Location.” 

One common approach to named entity recognition is to use a rule-based system, where a set of pre-defined rules are applied to the text. This approach can be effective, but it’s also limited in its ability to generalize to newly named entities not present in the rules or to handle complex language. 

Another approach is to use machine learning algorithms, which can learn to identify and categorize named entities from a large corpus of labelled training data. These algorithms can be trained to recognize a wide range of named entities and can handle complex language, making them a more robust and flexible solution for NER. 

Five Open-source NER Datasets 

Whether you’re a researcher looking for a dataset that can be used as a benchmark, or a practitioner in the field looking for a freely available dataset to bootstrap a NER model, here are 5 excellent resources to get started: 

• CoNLL-2003: Created for the CoNLL-2003 shared task on named entity recognition, this dataset includes over 200,000 tokens of newspaper text in English with annotations for entities such as person names, organizations, and locations. 
• ACE 2004: A collection of English newswire articles that have been annotated for names and other entities such as events and relationships. The dataset includes over 300,000 tokens of text and covers a wide range of named entity types. 
• WNUT 2016: A collection of social media posts annotated for named entities with a focus on difficult to recognize entities in informal text, such as named entities that are misspelled or that use non-standard forms. 
• OntoNotes 5.0: A large-scale corpus of text annotated for a wide range of named entities and other linguistic phenomena. The dataset includes over 1.5 million tokens of text and covers multiple languages, including English, Chinese, and Arabic. 
• Twitter NER Corpus: A collection of tweets annotated for named entities with a focus relevant to Twitter’s context, such as hashtags and user mentions. The dataset includes over 100,000 tokens and provides a useful resource for researchers specializing in NER for social media text. 

Advantages and Disadvantages of Open-source Datasets 

Open-source NER datasets have both advantages and disadvantages: on the one hand, they can be freely used, shared, and modified by anyone, making them a valuable resource for NLP researchers and practitioners, allowing for easy collaboration and the sharing of ideas within the NLP community. 

However, open-source NER datasets also have potential drawbacks: for example, data collection may not have been done ethically with the proper consent of the data’s contributors. Additionally, data quality in open-source NER datasets may vary, as they’re often annotated by volunteers and not subject to the rigorous quality controls of commercially collected datasets. 

Furthermore, open-source NER datasets may only sometimes have adequate data protection measures in place, leaving individuals’ personal information vulnerable. This can be a concern, especially for datasets that include sensitive information such as medical records or financial data and/or include protected classes such as children. 

In addition to the above, it’s also important to ensure that the domain of the open-source NER dataset matches the intended use case. For example, a dataset containing legal filings wouldn’t be suitable for a project related to financial transactions. 

An alternative to using open-source NER datasets is to purchase high-quality datasets from a reputable provider. Defined.ai offers off-the-shelf NER datasets that are ethically sourced with proper contributor consent and subjected to rigorous quality checks, ensuring ethical collection and reliability. In addition, Defined.ai also offers custom solutions at scale for any NER project, allowing businesses to access high-quality data and support for their specific needs. 

It’s important to carefully evaluate your options and choose a dataset or solution that meets the unique requirements of your NER project while also considering ethical and privacy concerns. Thankfully, you don’t need to do this alone, as Defined.ai has a tailor-made, ethical solution perfectly suited to your needs.