Seth Hendrickson created SPARK-17748:
----------------------------------------

             Summary: One-pass algorithm for linear regression with L1 and 
elastic-net penalties
                 Key: SPARK-17748
                 URL: https://issues.apache.org/jira/browse/SPARK-17748
             Project: Spark
          Issue Type: Bug
          Components: ML
            Reporter: Seth Hendrickson


Currently linear regression uses weighted least squares to solve the normal 
equations locally on the driver when the dimensionality is small (<4096). 
Weighted least squares uses a Cholesky decomposition to solve the problem with 
L2 regularization (which has a closed-form solution). We can support 
L1/elasticnet penalties by solving the equations locally using OWL-QN solver.

Also note that Cholesky does not handle singular covariance matrices, but 
L-BFGS and OWL-QN are capable of providing reasonable solutions. This patch can 
also add support for solving singular covariance matrices by also adding L-BFGS.



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)

---------------------------------------------------------------------
To unsubscribe, e-mail: [email protected]
For additional commands, e-mail: [email protected]

Reply via email to