Podcast
Questions and Answers
What is the main purpose of factor analysis of the document-term matrix?
What is the main purpose of factor analysis of the document-term matrix?
To determine the similarity of words based on the documents they cooccur in and the similarity of documents based on the words they contain.
What does Singular Value Decomposition (SVD) help in achieving in the context of document-term matrix?
What does Singular Value Decomposition (SVD) help in achieving in the context of document-term matrix?
It helps in obtaining the best (least-squares) approximation by truncating the matrix to topics.
How can the complexity of SVD on a matrix be reduced?
How can the complexity of SVD on a matrix be reduced?
By approximating it using Monte-Carlo sampling if only a certain number of components are needed.
What is the key idea behind the probabilistic topic modeling?
What is the key idea behind the probabilistic topic modeling?
What does a probabilistic topic model entail for every document and word?
What does a probabilistic topic model entail for every document and word?
Does SVD yield probabilities directly? Explain.
Does SVD yield probabilities directly? Explain.
What is the main goal of topic modeling in relation to a text corpus?
What is the main goal of topic modeling in relation to a text corpus?
How does Latent Semantic Indexing (LSI) or Latent Semantic Analysis (LSA) help in information retrieval?
How does Latent Semantic Indexing (LSI) or Latent Semantic Analysis (LSA) help in information retrieval?
What distinguishes topic modeling from clustering in terms of emphasis?
What distinguishes topic modeling from clustering in terms of emphasis?
Why is exact search problematic in information retrieval when dealing with synonymy and polysemy?
Why is exact search problematic in information retrieval when dealing with synonymy and polysemy?
What is the purpose of identifying 'factors' in Latent Semantic Indexing for document representation?
What is the purpose of identifying 'factors' in Latent Semantic Indexing for document representation?
