Machine Learning

, Volume 68, Issue 3, pp 267–276 | Cite as

A note on Platt’s probabilistic outputs for support vector machines

  • Hsuan-Tien Lin
  • Chih-Jen Lin
  • Ruby C. Weng


Platt’s probabilistic outputs for Support Vector Machines (Platt, J. in Smola, A., et al. (eds.) Advances in large margin classifiers. Cambridge, 2000) has been popular for applications that require posterior class probabilities. In this note, we propose an improved algorithm that theoretically converges and avoids numerical difficulties. A simple and ready-to-use pseudo code is included.


Support vector machine Posterior probability 


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Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  1. 1.Department of Computer Science and Information EngineeringNational Taiwan UniversityTaipeiTaiwan
  2. 2.Department of StatisticsNational Chengchi UniversityTaipeiTaiwan

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