Matroid Online Bipartite Matching and Vertex Cover

The Adwords and Online Bipartite Matching problems have enjoyed a renewed attention over the past decade due to their connection to Internet advertising. Our community has contributed, among other things, new models (notably stochastic) and extensions to the classical formulations to address the issues that arise from practical needs. In this paper, we propose a new generalization based on matroids and show that many of the previous results extend to this more general setting. Because of the rich structures and expressive power of matroids, our new setting is potentially of interest both in theory and in practice. In the classical version of the problem, the offline side of a bipartite graph is known initially while vertices from the online side arrive one at a time along with their incident edges. The objective is to maintain a decent approximate matching from which no edge can be removed. Our generalization, called Matroid Online Bipartite Matching, additionally requires that the set of matched offline vertices be independent in a given matroid. In particular, the case of partition matroids corresponds to the natural scenario where each advertiser manages multiple ads with a fixed total budget. Our algorithms attain the same performance as the classical version of the problems considered, which are often provably the best possible. We present $1-1/e$-competitive algorithms for Matroid Online Bipartite Matching under the small bid assumption, as well as a $1-1/e$-competitive algorithm for Matroid Online Bipartite Matching in the random arrival model. A key technical ingredient of our results is a carefully designed primal-dual waterfilling procedure that accommodates for matroid constraints. This is inspired by the extension of our recent charging scheme for Online Bipartite Vertex Cover.Comment: 19 pages, to appear in EC'1

Understanding the Detection of View Fraud in Video Content Portals

While substantial effort has been devoted to understand fraudulent activity in traditional online advertising (search and banner), more recent forms such as video ads have received little attention. The understanding and identification of fraudulent activity (i.e., fake views) in video ads for advertisers, is complicated as they rely exclusively on the detection mechanisms deployed by video hosting portals. In this context, the development of independent tools able to monitor and audit the fidelity of these systems are missing today and needed by both industry and regulators. In this paper we present a first set of tools to serve this purpose. Using our tools, we evaluate the performance of the audit systems of five major online video portals. Our results reveal that YouTube's detection system significantly outperforms all the others. Despite this, a systematic evaluation indicates that it may still be susceptible to simple attacks. Furthermore, we find that YouTube penalizes its videos' public and monetized view counters differently, the former being more aggressive. This means that views identified as fake and discounted from the public view counter are still monetized. We speculate that even though YouTube's policy puts in lots of effort to compensate users after an attack is discovered, this practice places the burden of the risk on the advertisers, who pay to get their ads displayed.Comment: To appear in WWW 2016, Montr\'eal, Qu\'ebec, Canada. Please cite the conference version of this pape

Multiplicative Bidding in Online Advertising

In this paper, we initiate the study of the multiplicative bidding language adopted by major Internet search companies. In multiplicative bidding, the effective bid on a particular search auction is the product of a base bid and bid adjustments that are dependent on features of the search (for example, the geographic location of the user, or the platform on which the search is conducted). We consider the task faced by the advertiser when setting these bid adjustments, and establish a foundational optimization problem that captures the core difficulty of bidding under this language. We give matching algorithmic and approximation hardness results for this problem; these results are against an information-theoretic bound, and thus have implications on the power of the multiplicative bidding language itself. Inspired by empirical studies of search engine price data, we then codify the relevant restrictions of the problem, and give further algorithmic and hardness results. Our main technical contribution is an $O(\log n)$-approximation for the case of multiplicative prices and monotone values. We also provide empirical validations of our problem restrictions, and test our algorithms on real data against natural benchmarks. Our experiments show that they perform favorably compared with the baseline.Comment: 25 pages; accepted to EC'1

Keywords Advertising: Issues of Trademark Infringement

The Internet has become a crucial advertising tool for modern-day businesses. Increasingly, business enterprises are opting for online presence, and this phenomenon has significantly transformed advertising techniques. Consumers wish to spend less time and gain optimal results whilst searching for products and services on the Internet. In this setting, enterprising entities, such as Google, have sought to make maximum use of the need for online presence which has given rise to Internet advertising schemes such as Google’s ‘AdWords. The purpose of this paper is to assess the merits (or otherwise) of the recent ruling of the European Court of Justice (ECJ) in Google v Louis Vuitton. The analysis will compare it with the approach of courts in the United States and also draw on English jurisprudence. The discussion undertaken by this paper is topical given the recent decision of the French Supreme Court (Cour de Cassation) which appears to have followed the reasoning of the ECJ. The topicality is heightened given the absence of judicial precedence in France, and the decision to remand the cases back to the Court of Appeal for a case by case decision on Google’s civil liability

Technical, Automatic and Passive: Liability of Search Engines for Hosting Infringing Content in the Light of the Google Ruling

The present contribution discusses the latest ruling of the European Court of Justice in the case of Google, which may have deeper consequences for advertisers relying on AdWords service, as well as for providers of similar services around the globe. The Court ruling may turn out to be even more important for Web 2.0 service providers as it seems to have opened the possibility of applying for a legal protection under Article 14 of the Ecommerce Directive. European judges made it clear that sponsored links services are information society services and that they may fall under the sphere of application of hosting safe haven provided that their activities are of technical, automatic and passive nature understood as a lack of knowledge or control over the data stored. This statement is yet to be applied by French courts that will have to establish whether Google AdWords service is really neutral and hence deserves a special legal treatment

A Novel Approach for Bidding on Newly Set-Up Search Engine Advertising Campaigns

Advertisers setting up search engine advertising campaigns for the first time need to place bids on keywords, but typically lack experience and data to determine ranks that maximize a keyword's profit (generally referred to as a cold-start problem). This article aims at solving the problem of bidding on keywords in newly set-up search engine advertising campaigns. We suggest that advertisers collect data from the Google Keyword Planner to obtain precise estimates of the percentage increases in prices per click and clickthrough rates, which are needed to calculate optimal bids (exact approach). Together with the profit contribution per conversion and the conversion rate, the advertiser might then set bids that maximize profit. In case advertisers cannot afford to collect the required data, we suggest two proxy approaches and evaluate their performance using the exact approach as a benchmark. The empirical study shows that both proxy approaches perform reasonably well-the easier approach to implement (proxy 2) sometimes performs even better than the more sophisticated one (proxy 1). As a consequence, advertisers might just use this very simple proxy when bidding on keywords in newly set-up SEA campaigns. This research extends the stream of literature on how to determine optimal bids, which so far focuses on campaigns that are already running and where the required data to calculate bids is already available. This research offers a novel approach of determining bids when advertisers lack the aforementioned information

Google Adwords: Trademark Infringer or Trade Liberalizer

Google is the world\u27s most preferred search engine, with an audience share of eighty percent of Internet users worldwide. With so many people browsing its search results, Google is a natural advertising vehicle, and it has exploited this quality to become one of the most profitable Internet companies in U.S. history. However, success has not come without controversy, and one of the most significant concerns Google AdWords, which displays keyword-triggered ads and sponsored links alongside non-sponsored search results. AdWords has come under attack in the United States and in the European Union ( EU ) for its role in trademark infringement on the Internet, forcing courts to confront the clash of pre-Internet trademark infringement doctrines with new technology. Courts wish to be sensitive to the claims of trademark holders, but are reluctant to harm the essential functions of Google, which has become integral to Internet structure and capability. In addition, they have struggled with trademark protection\u27s traditional foundation in a world of physical boundaries when the Internet has rendered such barriers largely meaningless.[...] Part I of this Note outlines how Google AdWords uses keywords to generate online advertisements, explains where trademarked terms can enter this process, and how Google\u27s legal policy approaches the use of such terms. Part II summarizes the current state of U.S. trademark law and policy with respect to keyword-triggered online ad programs, and Part III summarizes the same with respect to the EU. Part IV argues that the United States and the EU should coordinate international efforts to legitimize through legislation certain uses of trademarked terms by search engines in order to avoid inefficient balkanization of the Internet, and to protect a search engine\u27s capability to encourage trade liberalization