The “ Priority Algorithm” is a model of computation introduced by Borodin, Nielsen and Rackoff [BNR03] which formulates a wide class of greedy algorithms. For an arbitrary set S of jobs, we are interested in whether or not there exists a priority algorithm that gains optimal profit on every subset of S. In the case where the jobs are all intervals, we characterize such sets S and give an effici...

We apply the superfast divide-and-conquer MBA algorithm to possibly singular n × n Toeplitz-like integer input matrices and extend it to computations in the ring of integers modulo a power of a random prime. We choose the power which barely fits the size of a computer word; this saves word operations in the subsequent lifting steps. We extend our early techniques for avoiding degeneration while...

In this paper we propose an efficient approach to the compressed string matching problem on Huffman encoded texts, based on the Boyer-Moore strategy. Once a candidate valid shift has been located, a subsequent verification phase checks whether the shift is codeword aligned by taking advantage of the skeleton tree data structure. Our approach leads to algorithms that exhibit a sublinear behavior...

The Cooley-Tukey FFT algorithm decomposes a discrete Fourier transform (DFT) of size n = km into smaller DFTs of size k and m. In this paper we present a theorem that decomposes a polynomial transform into smaller polynomial transforms, and show that the FFT is obtained as a special case. Then we use this theorem to derive a new class of recursive algorithms for the discrete cosine transforms (...

We study minimum distance estimation problems related to maximum likelihood estimation in positron emission tomography (pet), which admit algorithms similar to the standard em algorithm for pet with the same type of monotonicity properties as does the em algorithm, see Vardi, Shepp, and Kaufman [25]. We derive the algorithms via the majorizing function approach of De Pierro [11], as well as via...

We present two new algorithms for searching in sorted X+Y +R+S, one based on heaps and the other on sampling. Each of the algorithms runs in time O(n 2 logn) (n being the size of the sorted arrays X, Y , R and S). Hence in each case, by constructing arrays of size n = O(2 s=4), we obtain a new algorithm for solving certain NP-Complete problems such as Knapsack on s data items in time equal (up ...

Learning to rank is a supervised learning problem where the output space is the space of rankings but the supervision space is the space of relevance scores. We make theoretical contributions to the learning to rank problem both in the online and batch settings. First, we propose a perceptron-like algorithm for learning a ranking function in an online setting. Our algorithm is an extension of t...

Abstract. Satellite estimates of surface UV irradiance have been available since 1978 from the TOMS spectrometer and continued with significantly improved ground resolution using Ozone Monitoring Instrument (OMI 2004–current) Sentinel 5 Precursor (S5P 2017–current). The retrieval algorithm remains essentially same: it first clear-sky based on measured ozone then accounts for attenuation by clou...