Abstract: A system and method are described for recognizing repeated audio material within at least one media stream without prior knowledge of the nature of the repeated material. The system and method are able to create a screening database from the media stream or streams. An unknown sample audio fragment is taken from the media stream and compared against the screening database to find if there are matching fragments within the media streams by determining if the unknown sample matches any samples in the screening database.

Abstract: A facility for selecting advertising outlets on which to place advertising messages for an advertiser is described. For each of a first group of advertising outlets, the facility assesses the rate at which visitors to the advertiser also visit the advertising outlet. The facility selects an advertising outlet among the first group having the highest assessed rate. For each of a second group of advertising outlets, the facility assesses the tendency of a high-performing advertising outlet to drive its visitors to the advertising outlet among the second group of advertising outlets. The facility selects an advertising outlet among the second group to which the high-performing advertising outlet has the greatest assessed tendency to drive its visitors.