16. A system, comprising: a data store storing sets of duplicate keywords for an advertising account, each set of duplicate keywords including keywords having common matching text for the set; and a duplicate keyword selection system comprising one or more processors configured to: identify two or more different sets of duplicate keywords including duplicate keywords that satisfy a selection criterion; receive a single action request to modify an attribute value of a proper subset of duplicate keywords in each of the identified two or more different sets of duplicate keywords, the proper subset of duplicate keywords in each of the two or more different sets of duplicate keywords being only those keywords that satisfy the selection criterion; and modify, within each particular set of the two or more different sets of duplicate keywords, attribute values for the proper subset of duplicate keywords in the particular set, the modification being performed in response to the single action request.
16. A system, comprising: a data store storing sets of duplicate keywords for an advertising account, each set of duplicate keywords including keywords having common matching text for the set; and a duplicate keyword selection system comprising one or more processors configured to: identify two or more different sets of duplicate keywords including duplicate keywords that satisfy a selection criterion; receive a single action request to modify an attribute value of a proper subset of duplicate keywords in each of the identified two or more different sets of duplicate keywords, the proper subset of duplicate keywords in each of the two or more different sets of duplicate keywords being only those keywords that satisfy the selection criterion; and modify, within each particular set of the two or more different sets of duplicate keywords, attribute values for the proper subset of duplicate keywords in the particular set, the modification being performed in response to the single action request. 22. The system of claim 16 , wherein the selection criterion specifies a relative attribute value for at least one attribute selected from a group consisting of a quality score, a keyword word count, a targeting match type, an advertisement group to which each keyword belongs, a status of each keyword specifying whether the keyword is active or paused, a status of the advertisement group, and a campaign to which each keyword belongs.