Abstract: An online system suggests targeting criteria to advertisers creating new ads in the online system by generating a seed group of targeting criteria. The seed targeting criteria include targeting criteria already selected (if any), targeting criteria previously used, and targeting criteria extracted from the ad being created (e.g., from ad components) or a page being promoted by the ad. The seed targeting criteria are expanded via collaborative filtering on advertisers, collaborative filtering on targeted users, and determination of relationships within topic hierarchies. The online system selects a subset of the expanded targeting criteria by applying a machine learning model to each targeting criterion to determine a probability of the advertiser selecting the targeting criterion if it were suggested. The targeting criteria are ranked based on the determined probabilities and selected based on the ranking. The suggested targeting criteria may also be ordered in the user interface based on the ranking.

Abstract: Disclosed are new organometallic complex molecules having light-emitting and electron-transporting characteristics. Also disclosed is organic EL (electroluminescent) devices using these organometallic complex molecules as electron-transporting materials. The organometallic complex molecules are used to form a light-emitting layer with or without doping of another light-emitting material. The organometallic complex molecules can also be used in an electron-transporting layer of the organic EL device. The organic EL devices incorporating the organometallic complex molecules have high thermal stability.