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https://issues.apache.org/jira/browse/MADLIB-640?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Frank McQuillan resolved MADLIB-640.
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    Resolution: Fixed

> SVM Novelty: Result is incorrect class which is "OUT"
> -----------------------------------------------------
>
>                 Key: MADLIB-640
>                 URL: https://issues.apache.org/jira/browse/MADLIB-640
>             Project: Apache MADlib
>          Issue Type: Bug
>            Reporter: Jiali Yao
>            Assignee: Rahul Iyer
>              Labels: severity_set
>             Fix For: v1.9.1
>
>
> We use data sets which class = 1 as "IN" and verify result in two side:
> 1.    All class = 1 items should be as marked as "IN"
> 2.    All class = -1 items should be as marked as "OUT"
> But in MADlib result, we can see that all items are marked as "IN".
> Below is one example: 
> {code}
> -- method: svm_nd_dot_ds_0_0_svm_novelty_detection_0
> SELECT madlib.svm_novelty_detection
>                         ( 'madlibtestdata.svm_a9a_in'::text     --input_table
>                         , 'madlibtestresult.nd_model_table'::text    
> --model_table
>                         , 'true'::boolean       --parallel
>                         , 'madlib.svm_dot'::text    --kernel_func
>                         , 'false'::boolean        --verbose
>                         , '0.01'::float8            --eta
>                         , '0.005'::float8             --nu
>                    ) AS q;
> -- All class should be return -1
> -- method: svm_nd_dot_ds_0_0_svm_nd_predict_score_3
> SELECT madlibtestdata.svm_nd_predict_score
>                         ( 'madlibtestresult.nd_model_table'::text     
> --model_table
>                         , 'madlibtestdata.svm_a9a_out'::text     --input_table
>                         , 'true'::boolean        --parallel
>                    ) AS score;
> {code}
> Currently for this query all class return 1.
> Data sets name        TrainSize       TestSize        Attributes      
> Rate(1:-1)      Missing Source URL
> a9a   32561   16281   123     11687:37155     N       
> http://www.csie.ntu.edu.tw/~cjlin/libsvmtools/datasets/binary.html#a9a
> We have tested multiple datasets,
> Parallel = true: 
> 5/5 dataset on Gaussian return  score = 0 
> 5/5 dataset on Polyminal return  score = 0 
> 4/5 dataset on dot return  score = 0
> Parallel = false: 
> 5/5 dataset on Gaussian return  score = 0 
> 3/5 dataset on Polyminal return  score = 0 
> 1/5 dataset on dot return  score = 0
> When score > 0, we have one data set has better result than libsvm. 
> When in parallel = true, we use most vote model as select prediction value



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