2014 Information Theory and Applications Workshop (ITA)最新文献

{"title":"On discrete alphabets for the two-user Gaussian interference channel with one receiver lacking knowledge of the interfering codebook","authors":"Alex Dytso, Daniela Tuninetti, N. Devroye","doi":"10.1109/ITA.2014.6804258","DOIUrl":"https://doi.org/10.1109/ITA.2014.6804258","url":null,"abstract":"In multi-user information theory it is often assumed that every node in the network possesses all codebooks used in the network. This assumption is however impractical in distributed ad-hoc and cognitive networks. This work considers the two-user Gaussian Interference Channel with one Oblivious Receiver (G-IC-OR), i.e., one receiver lacks knowledge of the interfering cookbook while the other receiver knows both codebooks. We ask whether, and if so how much, the channel capacity of the G-IC-OR is reduced compared to that of the classical G-IC where both receivers know all codebooks. Intuitively, the oblivious receiver should not be able to jointly decode its intended message along with the unintended interfering message whose codebook is unavailable. We demonstrate that in strong and very strong interference, where joint decoding is capacity achieving for the classical G-IC, lack of codebook knowledge does not reduce performance in terms of generalized degrees of freedom (gDoF). Moreover, we show that the sum-capacity of the symmetric G-IC-OR is to within O(log(log(SNR))) of that of the classical G-IC. The key novelty of the proposed achievable scheme is the use of a discrete input alphabet for the non-oblivious transmitter, whose cardinality is appropriately chosen as a function of SNR.","PeriodicalId":338302,"journal":{"name":"2014 Information Theory and Applications Workshop (ITA)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-01-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128801434","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impact of regularization on spectral clustering","authors":"Antony Joseph, Bin Yu","doi":"10.1109/ITA.2014.6804241","DOIUrl":"https://doi.org/10.1109/ITA.2014.6804241","url":null,"abstract":"Summary form only given. Clustering in networks/graphs is an important problem with applications in the analysis of gene-gene interactions, social networks, text mining, to name a few. Spectral clustering is one of the more popular techniques for such purposes, chiefly due to its computational advantage and generality of application. The algorithm's generality arises from the fact that it is not tied to any modeling assumptions on the data, but is rooted in intuitive measures of community structure such as sparsest cut based measures (Hagen and Kahng (1992), Shi and Malik (2000), Ng. et. al (2002)).Here, we attempt to understand regularized form of spectral clustering. Our motivation for this work was empirical results in Amini et. al (2013) that showed that the performance of spectral clustering can greatly be improved via regularization. Here regularization entails adding a constant matrix to the adjacency matrix and calculating the corresponding Laplacian matrix. The value of the constant is called the regularization parameter. Our analysis is carried out under the stochastic block model (SBM) framework. Under the (SBM) (and its extensions). Previous results on spectral clustering (McSherry (2001), Dasgupta et. al. (2004), Rohe et. al (2011)) also assumed the SBM and relied on the minimum degree of the graph being sufficiently large to prove its good performance. By analyzing the spectrum of the Laplacian of an SBM as a function of the regularization parameter, we provide bounds for the perturbation of the regularized eigenvectors, which, in some situations, does not depend on the minimum degree. For example, in the two block SBM, our bounds depend inversely on the maximum degree, as opposed to the minimum degree. More importantly, we show the usefulness of regularization in the important practical situation where not all nodes can be clustered accurately. In such situations, in the absence of regularization, the top eigenvectors need not discriminate between the nodes which do belong to well-defined clusters. With a proper choice of regularization parameter, we demonstrate that top eigenvectors indeed discriminate between the well-defined clusters. A crucial ingredient in the above is the analysis of the spectrum of the Laplacian as a function of the regularization parameter. Assuming that there are K clusters, an adequate gap between the top K eigenvalues and the remaining eigenvalues, ensures that these clusters can be estimated well. Such a gap is commonly referred to as the eigen gap. In the situation considered in above paragraph, an adequate eigen gap may not exist for the unregularized Laplacian. We show that regularization works by creating a gap, allowing us to recover the clusters. As an important application of our bounds, we propose a data-driven technique DK-est (standing for estimated Davis-Kahn bounds) for choosing the regularization parameter. DK-est is shown to perform very well for simulated and real data sets.","PeriodicalId":338302,"journal":{"name":"2014 Information Theory and Applications Workshop (ITA)","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129686244","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Precise semidefinite programming formulation of atomic norm minimization for recovering d-dimensional (D ≥ 2) off-the-grid frequencies","authors":"Weiyu Xu, Jian-Feng Cai, K. Mishra, Myung Cho, A. Kruger","doi":"10.1109/ITA.2014.6804267","DOIUrl":"https://doi.org/10.1109/ITA.2014.6804267","url":null,"abstract":"Recent research in off-the-grid compressed sensing (CS) has demonstrated that, under certain conditions, one can successfully recover a spectrally sparse signal from a few time-domain samples even though the dictionary is continuous. In particular, atomic norm minimization was proposed in [1] to recover 1-dimensional spectrally sparse signal. However, in spite of existing research efforts [2], it was still an open problem how to formulate an equivalent positive semidefinite program for atomic norm minimization in recovering signals with d-dimensional (d ≥ 2) off-the-grid frequencies. In this paper, we settle this problem by proposing equivalent semidefinite programming formulations of atomic norm minimization to recover signals with d-dimensional (d ≥ 2) off-the-grid frequencies.","PeriodicalId":338302,"journal":{"name":"2014 Information Theory and Applications Workshop (ITA)","volume":"50 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126392440","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Non-asymptotic and asymptotic analyses on Markov chains in several problems","authors":"Masahito Hayashi, Shun Watanabe","doi":"10.1109/ITA.2014.6804255","DOIUrl":"https://doi.org/10.1109/ITA.2014.6804255","url":null,"abstract":"In this paper, we derive non-asymptotic achievability and converse bounds on the source coding with side-information and the random number generation with side-information. Our bounds are efficiently computable in the sense that the computational complexity does not depend on the block length. We also characterize the asymptotic behaviors of the large deviation regime and the moderate deviation regime by using our bounds, which implies that our bounds are asymptotically tight in those regimes. We also show the second order rates of those problems, and derive single letter forms of the variances characterizing the second order rates.","PeriodicalId":338302,"journal":{"name":"2014 Information Theory and Applications Workshop (ITA)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134355939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Closing the price of anarchy gap in the interdependent security game","authors":"Parinaz Naghizadeh Ardabili, M. Liu","doi":"10.1109/ITA.2014.6804216","DOIUrl":"https://doi.org/10.1109/ITA.2014.6804216","url":null,"abstract":"Investments in security technologies by strategic users is typically modeled as a public good problem, known as the Interdependent Security (IDS) game. The equilibria for such games are often inefficient, as selfish users free-ride on positive externalities of others' contributions. We present a mechanism that implements the socially optimal equilibrium in an IDS game through a message exchange process; this mechanism does not need to monitor or audit users. However, it does not necessarily guarantee voluntary participation, often a trivial condition to satisfy in many resource allocation problems, but made much harder due to the incentive to stay out and free-ride on others' investments. We discuss the role of cyber insurance in this setting.","PeriodicalId":338302,"journal":{"name":"2014 Information Theory and Applications Workshop (ITA)","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129469992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"On feedback in Gaussian multi-hop networks","authors":"Farzan Farnia, Ayfer Özgür","doi":"10.1109/ITA.2014.6804259","DOIUrl":"https://doi.org/10.1109/ITA.2014.6804259","url":null,"abstract":"The study of feedback has been mostly limited to single-hop communication settings. In this paper, we consider Gaussian networks where sources and destinations can communicate with the help of intermediate relays over multiple hops. We assume that links in the network can be bidirected providing opportunities for feedback. We ask the following question: can the information transfer in both directions of a link be critical to maximizing the end-to-end communication rates in the network? Equivalently, could one of the directions in each bidirected link (and more generally at least one of the links forming a cycle) be shut down and the capacity of the network still be approximately maintained? We show that in any arbitrary Gaussian network with bidirected edges and cycles, and unicast, multiple-access or broadcast traffic, we can always identify a directed acyclic subnetwork that approximately maintains the capacity of the original network. On the other hand, with multicast and multiple unicast traffic bidirected flow across links can be critical to maximizing the end-to-end capacity.","PeriodicalId":338302,"journal":{"name":"2014 Information Theory and Applications Workshop (ITA)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-04-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129860707","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assuring privacy and reliability in crowdsourcing with coding","authors":"L. Varshney, Aditya Vempaty, P. Varshney","doi":"10.1109/ITA.2014.6804213","DOIUrl":"https://doi.org/10.1109/ITA.2014.6804213","url":null,"abstract":"Crowd workers are often unreliable and anonymous. Hence there is a need to ensure reliable work delivery while preserving some level of privacy to the requester's data. For this purpose, we use a combination of random perturbation to mask the sensitive data and error-correcting codes for quality assurance. We also consider the possibility of collusion attacks by malicious crowd workers. We develop mathematical models to study the precise tradeoffs between task performance quality, level of privacy against collusion attacks, and cost of invoking a large crowd. Such a study provides design strategies and principles for crowd work. The use of classification codes may improve efficiency considerably. We also comment on the applicability of these techniques for scalable assessment in education via peer grading, e.g. for massive open online courses (MOOCs).","PeriodicalId":338302,"journal":{"name":"2014 Information Theory and Applications Workshop (ITA)","volume":"414 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124438050","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Enclosure letter [to TAB]","authors":"Mason Duan","doi":"10.1109/ita.2014.6804200","DOIUrl":"https://doi.org/10.1109/ita.2014.6804200","url":null,"abstract":"","PeriodicalId":338302,"journal":{"name":"2014 Information Theory and Applications Workshop (ITA)","volume":"285 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114673284","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}