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Introduction to LMNN and progress review . M.S. Student, Daewon Ko 07. 22. 2014. Contents. Definition of LMNN Schematic illustration of LMNN Algorithm of LMNN Current progress review of my research. Definition of LMNN. Large margin nearest neighbor(LMNN) classification
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Introduction to LMNN and progress review M.S. Student, DaewonKo 07. 22. 2014
Contents • Definition of LMNN • Schematic illustration of LMNN • Algorithm of LMNN • Current progress review of my research
Definition of LMNN • Large margin nearest neighbor(LMNN) classification : 1) a statistical machine learning algorithm. 2) it learns a Pseudo metric designed for k-nearest neighbor classification.
Definition of LMNN • Notation 1) Traing data 2) Set of possible class • Objective Leaning a pseudo metric of the type
Schematic illustration of LMNN Euclidean Metric Mahalanobis Metric Local neighborhood M Margin Similarly labeled(target neighbor) Differently labeled(impostor) Differently labeled(impostor)
Algorithm of LMNN LMNN optimizes the matrix M by semidefinte programming. For every data point , the target neighbors should be close and the impostors should be far away.
Algorithm of LMNN • The first optimization goal : minimizing the average distance between instances and their target neighbors • The second goal : constraining impostors to be one unit further away than target neighbors their resulting inequality constraint can be stated as:
Algorithm of LMNN • The final optimization becomes: s.t.