{"action":"created","issue":{"url":"https://api.github.com/repos/scikit-learn/scikit-learn/issues/4639","labels_url":"https://api.github.com/repos/scikit-learn/scikit-learn/issues/4639/labels{/name}","comments_url":"https://api.github.com/repos/scikit-learn/scikit-learn/issues/4639/comments","events_url":"https://api.github.com/repos/scikit-learn/scikit-learn/issues/4639/events","html_url":"https://github.com/scikit-learn/scikit-learn/issues/4639","id":71370103,"number":4639,"title":"Documentation of label-binarizer and multi-label format","user":{"login":"amueller","id":449558,"avatar_url":"https://avatars.githubusercontent.com/u/449558?v=3","gravatar_id":"","url":"https://api.github.com/users/amueller","html_url":"https://github.com/amueller","followers_url":"https://api.github.com/users/amueller/followers","following_url":"https://api.github.com/users/amueller/following{/other_user}","gists_url":"https://api.github.com/users/amueller/gists{/gist_id}","starred_url":"https://api.github.com/users/amueller/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/amueller/subscriptions","organizations_url":"https://api.github.com/users/amueller/orgs","repos_url":"https://api.github.com/users/amueller/repos","events_url":"https://api.github.com/users/amueller/events{/privacy}","received_events_url":"https://api.github.com/users/amueller/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/scikit-learn/scikit-learn/labels/Documentation","name":"Documentation","color":"0b02e1"},{"url":"https://api.github.com/repos/scikit-learn/scikit-learn/labels/Easy","name":"Easy","color":"02d7e1"},{"url":"https://api.github.com/repos/scikit-learn/scikit-learn/labels/Need%20Contributor","name":"Need Contributor","color":"009800"}],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":13,"created_at":"2015-04-27T18:52:36Z","updated_at":"2015-11-17T00:09:16Z","closed_at":null,"body":"From the docs I feel it is not entirely clear that using label indicators means doing multi-label classification.\r\nI think this should be better documented in the multi-class narratives, the OneVsRestClassifier and the LabelBinarizer.\r\nApplying a label-binarizer to your y will result in quite different results, which is obvious if you know that this will switch the problem to a multi-label problem, but is somewhat unintuitive for the uninitiated."},"comment":{"url":"https://api.github.com/repos/scikit-learn/scikit-learn/issues/comments/157215514","html_url":"https://github.com/scikit-learn/scikit-learn/issues/4639#issuecomment-157215514","issue_url":"https://api.github.com/repos/scikit-learn/scikit-learn/issues/4639","id":157215514,"user":{"login":"pieteradejong","id":1856262,"avatar_url":"https://avatars.githubusercontent.com/u/1856262?v=3","gravatar_id":"","url":"https://api.github.com/users/pieteradejong","html_url":"https://github.com/pieteradejong","followers_url":"https://api.github.com/users/pieteradejong/followers","following_url":"https://api.github.com/users/pieteradejong/following{/other_user}","gists_url":"https://api.github.com/users/pieteradejong/gists{/gist_id}","starred_url":"https://api.github.com/users/pieteradejong/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/pieteradejong/subscriptions","organizations_url":"https://api.github.com/users/pieteradejong/orgs","repos_url":"https://api.github.com/users/pieteradejong/repos","events_url":"https://api.github.com/users/pieteradejong/events{/privacy}","received_events_url":"https://api.github.com/users/pieteradejong/received_events","type":"User","site_admin":false},"created_at":"2015-11-17T00:09:16Z","updated_at":"2015-11-17T00:09:16Z","body":"@amueller does MultiLabelBinarizer also convert the other way, that is, from a binary matrix to a list of tuples? for example, from:\r\narray([[0, 0, 1, 1, 1],\r\n       [0, 0, 1, 0, 0],\r\n       [1, 1, 0, 1, 0],\r\n       [1, 1, 1, 1, 1],\r\n       [1, 1, 1, 0, 0]])\r\n\r\nto:\r\ny = [[2, 3, 4], [2], [0, 1, 3], [0, 1, 2, 3, 4], [0, 1, 2]]"}}