Browsing by Author "Kurt, Ali Emirhan"

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    Estimating distributions varying in time in a universal manner
    (IEEE, 2017) Gökçesu, Kaan; Manış, Eren; Kurt, Ali Emirhan; Yar, Ersin
    We investigate the estimation of distributions with time-varying parameters. We introduce an algorithm that achieves the optimal negative likelihood performance against the true probability distribution. We achieve this optimum regret performance without any knowledge about the total change of the parameters of true distribution. Our results are guaranteed to hold in an individual sequence manner such that we have no assumptions on the underlying sequences. Apart from the regret bounds, through synthetic and real life experiments, we demonstrate substantial performance gains with respect to the state-of-the-art probability density estimation algorithms in the literature.
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    Online anomaly detection in case of limited feedback with accurate distribution learning
    (IEEE, 2017) Marivani, Iman; Kari, Dariush; Kurt, Ali Emirhan; Manış, Eren
    We propose a high-performance algorithm for sequential anomaly detection. The proposed algorithm sequentially runs over data streams, accurately estimates the nominal distribution using exponential family and then declares an anomaly when the assigned likelihood of the current observation is less than a threshold. We use the estimated nominal distribution to assign a likelihood to the current observation and employ limited feedback from the end user to adjust the threshold. The high performance of our algorithm is due to accurate estimation of the nominal distribution, where we achieve this by preventing anomalous data to corrupt the update process. Our method is generic in the sense that it can operate successfully over a wide range of data distributions. We demonstrate the performance of our algorithm with respect to the state-of-the-art over time varying distributions.
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    Savaş sanatları ve kadın : Wing Chun ve yakın Türkiye tarihindeki gelişimi
    (Bilkent University, 2015) Manış, Eren; Doğaneli, Gizem; Kurt, Ali Emirhan; Arslan, Hatice Merve; Saner, Doğukan