Techniques for named entity recognition

Before we tackle the strategies for named entity recognition, we should differentiate between some similar terms that we will come across when doing this work. Usually, when English-speakers first begin to think about named entities, they assume named entities are just proper nouns. What is a proper noun? Proper nouns are typically capitalized in English, and refer to a specific named person, place, or thing. Proper names can include proper nouns as well as noun phrases. Alaska, Barack Obama, January, and The Grateful Dead are all proper names. Are all proper nouns and names capitalized? Not necessarily, as we saw with iPhone and iPad, and also eBay, and the author bell hooks. Are all capitalized nouns proper? No. For example, we write the Englishman came around for tea, where Englishman is capitalized, yet Englishman is a common noun in English.

NER is considerably more interesting than just recognizing nouns, or proper nouns. In a linguistic sense...