What is IF-IDF and why used?

Question

Accepted Answer

IF-IDF stands for Inverse Document Frequency - Term Frequency. It is used in information retrieval to measure the importance of a term in a document.

IF-IDF is a numerical statistic that reflects how important a word is to a document in a collection or corpus.
It is calculated by multiplying the term frequency (TF) by the inverse document frequency (IDF) of the term.
IF-IDF helps in identifying the most relevant words in a document by giving higher weights to terms that are rare in the corpus but common in the document.
It is commonly used in search engines for ranking search results based on relevance.
For example, in a document containing the word 'data' multiple times, IF-IDF would give higher weight to 'data' if it is rare in other documents in the corpus.

Popular interview questions of Data Scientist