I am just expanding my horizons out from Google and so am unfamiliar with the Yahoo interface at the moment. I am able to set individual keywords to advanced or standard match but cannot see what the setting is from the adgroup page. Do I really have to go to the individual keyword's page in order to view its match type? Also is it possible to run both match types for a single keyword within the same adgroup?
I believe that standard match and advanced match apply to the entire account. (access in administration tab) However, you may switch between match types per campaign. ("arrow button next to "campaign settings" - "tactic settings" - right hand side of campaign page). I'm not sure if you can set match types for individual key words. I would suggest that you download your campaign, switch match types for individual key words and attempt to do a bulk import to see if it works.