Auto-encoder Text Retrieval Vector Space Model Bag-of-word this is 1 word string: query “This is an apple'”e 0 an 1 apple 1 pen 0 document Semantics are not considered.Auto-encoder – Text Retrieval word string: “This is an apple” … this is a an apple pen 1 1 0 1 1 0 Bag-of-word Semantics are not considered. Vector Space Model document query