Hi wang-san. # I detach this topic and modified the subject.
> Do you know the meaning of option "complementary" using mahout to build the > random forest? Sorry, I cannot get your point clearly, but do you talk about the Pruning and the Grafting? Regards, 2012/2/7 Wang Yue (Commented) (JIRA) <[email protected]>: > > [ > https://issues.apache.org/jira/browse/MAHOUT-945?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13201399#comment-13201399 > ] > > Wang Yue commented on MAHOUT-945: > --------------------------------- > > Hi, Mukai > Thanks for your efforts. I feel it is ok for your modification. I have a > question about the decision tree building. > Do you know the meaning of option "complementary" using mahout to build > the random forest? > > On Mon, Jan 23, 2012 at 6:55 AM, Ikumasa Mukai (Updated) (JIRA) < > > > > -- > Regards, Wang Yue > PhD Starts From 08 Fall > NUS Graduate School for Integrative Sciences and Engineering, NUS > Email: [email protected] > Homepage: https://sites.google.com/site/fayue1015/ > HP: +65 81022515 > > >> The variance calculation of Random forest regression tree >> --------------------------------------------------------- >> >> Key: MAHOUT-945 >> URL: https://issues.apache.org/jira/browse/MAHOUT-945 >> Project: Mahout >> Issue Type: Improvement >> Components: Classification >> Affects Versions: 0.6 >> Reporter: Wang Yue >> Labels: Regressionsplit.java >> Attachments: MAHOUT-945.patch, MAHOUT-945.patch >> >> Original Estimate: 48h >> Remaining Estimate: 48h >> >> Hi, Mukai >> Thanks for your efforts in expand the RF to regression. However, I have a >> doubt about your implementation regarding to Regressionsplit.java. The >> variance method >> " >> private static double variance(double[] s, double[] ss, double[] dataSize) { >> double var = 0; >> for (int i = 0; i < s.length; i++) { >> if (dataSize[i] > 0) { >> var += ss[i] - ((s[i] * s[i]) / dataSize[i]); >> } >> } >> return var; >> } >> " >> While the variance in my mind should be something like >> var += ss[i]/dataSize[i] - ((s[i] * s[i]) / (dataSize[i]*dataSize[i])); >> Please help correct me if I am wrong. Thanks > > -- > This message is automatically generated by JIRA. > If you think it was sent incorrectly, please contact your JIRA > administrators: > https://issues.apache.org/jira/secure/ContactAdministrators!default.jspa > For more information on JIRA, see: http://www.atlassian.com/software/jira > > -- - - - - - - - IKumasa Mukai at Recruit Co.,Ltd.
