Author Archives: Ashok Chilakapati

Attention as Adaptive Tf-Idf for Deep Learning

Attention is like tf-idf for deep learning. Both attention and tf-idf boost the importance of some words over others. But while tf-idf weight vectors are static for a set of documents, the attention weight vectors will adapt depending on the particular classification objective. Attention derives larger weights for those words that are influencing the classification objective, thus opening a window into the decision making process with in the deep learning blackbox…

Concept Drift and Model Decay in Machine Learning

Concept drift is a drift of labels with time for the essentially the same data. It leads to the divergence of decision boundary for new data from that of a model built from earlier data/labels. Scoring randomly sampled new data can detect the drift allowing us to trigger the expensive re-label/re-train tasks on an as needed basis…

Word Bags vs Word Sequences for Text Classification

Sequence respecting approaches have an edge over bag-of-words implementations when the said sequence is material to classification. Long Short Term Memory (LSTM) neural nets with words sequences are evaluated against Naive Bayes with tf-idf vectors on a synthetic text corpus for classification effectiveness.