{"action":"reopened","issue":{"url":"https://api.github.com/repos/markmfredrickson/optmatch/issues/101","labels_url":"https://api.github.com/repos/markmfredrickson/optmatch/issues/101/labels{/name}","comments_url":"https://api.github.com/repos/markmfredrickson/optmatch/issues/101/comments","events_url":"https://api.github.com/repos/markmfredrickson/optmatch/issues/101/events","html_url":"https://github.com/markmfredrickson/optmatch/issues/101","id":77150935,"number":101,"title":"In `match_on.glm` interpret use of `strata` as call for exact matching ","user":{"login":"benthestatistician","id":827606,"avatar_url":"https://avatars.githubusercontent.com/u/827606?v=3","gravatar_id":"","url":"https://api.github.com/users/benthestatistician","html_url":"https://github.com/benthestatistician","followers_url":"https://api.github.com/users/benthestatistician/followers","following_url":"https://api.github.com/users/benthestatistician/following{/other_user}","gists_url":"https://api.github.com/users/benthestatistician/gists{/gist_id}","starred_url":"https://api.github.com/users/benthestatistician/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/benthestatistician/subscriptions","organizations_url":"https://api.github.com/users/benthestatistician/orgs","repos_url":"https://api.github.com/users/benthestatistician/repos","events_url":"https://api.github.com/users/benthestatistician/events{/privacy}","received_events_url":"https://api.github.com/users/benthestatistician/received_events","type":"User","site_admin":false},"labels":[{"url":"https://api.github.com/repos/markmfredrickson/optmatch/labels/feature","name":"feature","color":"0b02e1"}],"state":"open","locked":false,"assignee":{"login":"josherrickson","id":1674171,"avatar_url":"https://avatars.githubusercontent.com/u/1674171?v=3","gravatar_id":"","url":"https://api.github.com/users/josherrickson","html_url":"https://github.com/josherrickson","followers_url":"https://api.github.com/users/josherrickson/followers","following_url":"https://api.github.com/users/josherrickson/following{/other_user}","gists_url":"https://api.github.com/users/josherrickson/gists{/gist_id}","starred_url":"https://api.github.com/users/josherrickson/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/josherrickson/subscriptions","organizations_url":"https://api.github.com/users/josherrickson/orgs","repos_url":"https://api.github.com/users/josherrickson/repos","events_url":"https://api.github.com/users/josherrickson/events{/privacy}","received_events_url":"https://api.github.com/users/josherrickson/received_events","type":"User","site_admin":false},"milestone":null,"comments":4,"created_at":"2015-05-16T22:44:12Z","updated_at":"2015-06-16T19:42:13Z","closed_at":null,"body":"In glm formulas one can wrap a nominal independent variable in `strata`, without changing the result:\r\n````\r\n> aglm2 <- glm(pr~.-cost-ne+strata(ne), data=nuclearplants, family=binomial)\r\n> aglm <- glm(pr~.-cost, data=nuclearplants, family=binomial)\r\n> all.equal(predict(aglm), predict(aglm2))\r\n[1] TRUE\r\n````\r\nAs I understand it, the purpose of the `strata` command is purely to leave signals for methods and functions that will operate on the fitted glm.  Let's use it as a signal that the user wanted her propensity score matching to incorporate exact matching on the argument of `strata`.\r\n\r\n(Taken together with the feature requested in #86, this would relieve nearly all end users of having to call `exactMatch` directly, or having to muck around directly with ISMs, in order to subdivide matching problems.)"}}