Revision as of 17:36, 26 November 2013 edit Brycehughes (talk \| contribs) Autopatrolled, Extended confirmed users, Page movers, IP block exemptions, Pending changes reviewers, Rollbackers 26,267 edits Reverted to revision 580850245 by Brycehughes (talk): Rvv. ← Previous edit		Revision as of 13:11, 29 April 2014 edit undo Anishpatel0 (talk \| contribs) 10 edits →Weighted Incremental Algorithm Alternative Incorrect: new section Next edit →
Line 485: [[Special:Contributions/208.77.214.129\|208.77.214.129]] ([[User talk:208.77.214.129\|talk]]) 21:02, 3 June 2013 (UTC) == Weighted Incremental Algorithm Alternative Incorrect == <source lang="python"> def weighted_incremental_variance(dataWeightPairs): ... M2 = M2 + sumweight * delta * R # Alternatively, "M2 = M2 + weight * delta * (x−mean)" ... </source> I did the math to see if the stated update formula is indeed correct with the alternative mentioned in the comment; I have found that it is not. As such, I propose the alternative comment be removed. If anyone would like me to do show the math of why there are not equivalent, let me know. Basically, the alternative confuses the sumweight of the previous iteration and the sumweight of the current iteration (which is updated after M2 is calculated).

Talk:Algorithms for calculating variance: Difference between revisions