Evaluating the results quantitatively
There are many different techniques for evaluating the quality and the relevancy of the captions generated. We will briefly discuss several such metrics we can use to evaluate the captions. We will discuss four metrics: BLEU, ROGUE, METEOR, and CIDEr. All these measures share a key objective, to measure the adequacy (meaning of generated text) and fluency (grammatical correctness of text) in the generated text. To calculate all these measures, we will use a candidate sentence and a reference sentence, where a candidate sentence is the sentence/phrase predicted by our algorithm and the reference sentence is the true sentence/phrase we want to compare with.
BLEU
Bilingual Evaluation Understudy (BLEU) was proposed by Papineni and others in BLEU: A Method for Automatic Evaluation of Machine Translation, Proceedings of the 40th Annual Meeting of the Association for Computational Linguistics (ACL), Philadelphia, July (2002): 311-318. It measures the n-gram...