human: Given a hyperedge-centered hypergraph: <hypergraph>, where the center hyperedge is induced by one source paper and its member nodes are the cited papers.

Details of the hypergraph:
Center hyperedge (induced by source paper "measuring ad value without bankrupting user privacy"):
  Abstract: Recent work has demonstrated that by monitoring the Real Time Bidding (RTB) protocol, one can estimate the monetary worth of different users for the programmatic advertising ecosystem, even when the so-called winning bids are encrypted. In this paper we describe how to implement the above techniques in a practical and privacy preserving manner. Specifically, we study the privacy consequences of reporting back to a centralized server, features that are necessary for estimating the value of encrypted winning bids. We show that by appropriately modulating the granularity of the necessary information and by scrambling the communication channel to the server, one can increase the privacy performance of the system in terms of K-anonymity. We've implemented the above ideas on a browser extension and disseminated it to some 200 users. Analyzing the results from 6 months of deployment, we show that the average value of users for the programmatic advertising ecosystem has grown more than 75% in the last 3 years.

Includes members:
  Member "cookie synchronization everything you always wanted to know but were afraid to ask":
    also connected through other hyperedges:
      - Hyperedge HE-1 (induced by source paper "stop tracking me bro differential tracking of user demographics on hyper partisan websites")
  Member "tracing information flows between ad exchanges using retargeted ads":
    also connected through other hyperedges:
      - Hyperedge HE-2 (induced by source paper "stop tracking me bro differential tracking of user demographics on hyper partisan websites")
  Member "facebook use of sensitive data for advertising in europe":
    also connected through other hyperedges:
      - Hyperedge HE-3 (induced by source paper "facebook ads as a demographic tool to measure the urban rural divide")
  Member "money walks a human centric study on the economics of personal mobile data":
    also connected through other hyperedges:
      - Hyperedge HE-4 (induced by source paper "no more chasing waterfalls a measurement study of the header bidding ad ecosystem")
  Member "your browsing behavior for a big mac economics of personal information online":
    also connected through other hyperedges:
      - Hyperedge HE-5 (induced by source paper "no more chasing waterfalls a measurement study of the header bidding ad ecosystem")

Question: Please tell me which class the source paper belongs to. The 40 classes are: cs.NA(Numerical Analysis), cs.MM(Multimedia), cs.LO(Logic in Computer Science), cs.CY(Computers and Society), cs.CR(Cryptography and Security), cs.DC(Distributed, Parallel, and Cluster Computing), cs.HC(Human-Computer Interaction), cs.CE(Computational Engineering, Finance, and Science), cs.NI(Networking and Internet Architecture), cs.CC(Computational Complexity), cs.AI(Artificial Intelligence), cs.MA(Multiagent Systems), cs.GL(General Literature), cs.NE(Neural and Evolutionary Computing), cs.SC(Symbolic Computation), cs.AR(Hardware Architecture), cs.CV(Computer Vision and Pattern Recognition), cs.GR(Graphics), cs.ET(Emerging Technologies), cs.SY(Systems and Control), cs.CG(Computational Geometry), cs.OH(Other Computer Science), cs.PL(Programming Languages), cs.SE(Software Engineering), cs.LG(Machine Learning), cs.SD(Sound), cs.SI(Social and Information Networks), cs.RO(Robotics), cs.IT(Information Theory), cs.PF(Performance), cs.CL(Computation and Language), cs.IR(Information Retrieval), cs.MS(Mathematical Software), cs.FL(Formal Languages and Automata Theory), cs.DS(Data Structures and Algorithms), cs.OS(Operating Systems), cs.GT(Computer Science and Game Theory), cs.DB(Databases), cs.DL(Digital Libraries), cs.DM(Discrete Mathematics). Directly output the class name.

gpt: cs.CR(Cryptography and Security)