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yuhao yang edited comment on SPARK-7514 at 5/11/15 6:41 AM: ------------------------------------------------------------ Thanks Joseph, just one concern for using center as it will change the core function from Normalized( x ) = (x - min) / (max - min) * scale + newBase to Normalized( x ) = ((x - min) / (max - min) - 0.5 )* scale + center which seems not as straightforward. Sure we can further discuss it over code. was (Author: yuhaoyan): Thanks Joseph, just one concern for using center as it will change the core function from Normalized( x ) = (x - min) / (max - min) * scale + newBase to Normalized( x ) = ((x - min) / (max - min) - 0.5 )* scale + center which seems be to not as straightforward. Sure we can further discuss it over code. > Add MinMaxScaler to feature transformation > ------------------------------------------ > > Key: SPARK-7514 > URL: https://issues.apache.org/jira/browse/SPARK-7514 > Project: Spark > Issue Type: New Feature > Components: MLlib > Reporter: yuhao yang > Original Estimate: 24h > Remaining Estimate: 24h > > Add a popular scaling method to feature component, which is commonly known as > min-max normalization or Rescaling. > Core function is, > Normalized( x ) = (x - min) / (max - min) * scale + newBase > where newBase and scale are parameters of the VectorTransformer. newBase is > the new minimum number for the feature, and scale controls the range after > transformation. This is a little complicated than the basic MinMax > normalization, yet it provides flexibility so that users can control the > range more specifically. like [0.1, 0.9] in some NN application. > for case that max == min, 0.5 is used as the raw value. > reference: > http://en.wikipedia.org/wiki/Feature_scaling > http://stn.spotfire.com/spotfire_client_help/index.htm#norm/norm_scale_between_0_and_1.htm -- This message was sent by Atlassian JIRA (v6.3.4#6332) --------------------------------------------------------------------- To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org For additional commands, e-mail: issues-h...@spark.apache.org