Named entity identification method and device

The invention discloses a named entity identification method and device. The method comprises the steps of obtaining a sentence sequence for model training and an annotation label sequence corresponding to the sentence sequence; converting the sentence sequence into vector representation of a sentence to obtain a vector of each character in the sentence sequence; generating a prediction vector according to the vector of the ith character and the prediction label of the (i-1) th character in the sentence sequence, and determining the prediction label of the ith character according to the prediction vector so as to generate a prediction label sequence corresponding to the sentence sequence; inputting the prediction tag sequence and the annotation tag sequence into a cross entropy loss function; and optimizing the cross entropy loss function by using a gradient descent algorithm to perform named entity recognition model training so as to perform named entity recognition according to the trained named entity reco