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https://issues.apache.org/jira/browse/SPARK-1585?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Patrick Wendell updated SPARK-1585:
-----------------------------------

    Fix Version/s:     (was: 1.0.0)
                   1.1.0

> Not robust Lasso causes Infinity on weights and losses
> ------------------------------------------------------
>
>                 Key: SPARK-1585
>                 URL: https://issues.apache.org/jira/browse/SPARK-1585
>             Project: Spark
>          Issue Type: Bug
>          Components: MLlib
>    Affects Versions: 0.9.1
>            Reporter: Xusen Yin
>            Assignee: Xusen Yin
>             Fix For: 1.1.0
>
>
> Lasso uses LeastSquaresGradient and L1Updater, but 
> diff = brzWeights.dot(brzData) - label
> in LeastSquaresGradient would cause too big diff, then will affect the 
> L1Updater, which increases weights exponentially. Small shrinkage value 
> cannot lasso weights back to zero then. Finally, the weights and losses reach 
> Infinity.
> For example, data = (0.5 repeats 10k times), weights = (0.6 repeats 10k 
> times), then data.dot(weights) approximates 300+, the diff will be 300. Then 
> L1Updater sets weights to approximate 300. In the next iteration, the weights 
> will be set to approximate 30000, and so on.



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