Pedro García

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The “interpretation” framework in pattern recognition (PR) arises in the many cases in which the more classical paradigm of “classification” is not properly applicable generally because the number of classes is rather large or simply because the concept of “class” does not hold. A very general way of representing the results of interpretations of given(More)
[ I l l V. N. Gupta, M. Lennig, and P. Mermelstein, “Fast search strategy in a large vocabulary word recognizer,” submitted to J. Acoust. Soc. Amer. [12] R. Schwartz, F. Kubala, 0. Kimball, P. Price, and J. Makhoul, “Improving performance of phonetic hidden Markov models in a continuous speech recognition system,” presented at the IEEE Workshop on Speech(More)
A k-Testable tree set in the Strict sense (k-TS) is essentially defined by a finite set of patterns of "size" k that are permitted to appear in the trees of the tree language. Given a positive sample S of trees over a ranked alphabet, an algorithm is proposed which obtains the smallest k-TS tree set containing S. The proposed algorithm is polynomial on the(More)
  • Alberto Cavallo, Maria Fazzolari, +4 authors Andrea Albagli Iruretagoyena
  • 2009
I use daily prices collected from online retailers in five countries to study the impact of measurement bias on three common price stickiness statistics. Relative to previous results, I find that online prices have longer durations, with fewer price changes close to zero, and hazard functions that initially increase over time. I show that time-averaging and(More)
The families of locally testable (LT ) and piecewise testable (PWT ) languages have been deeply studied in formal language theory. They have in common that the role played by the segments of length k of their words in the first family is played in the second by their subwords (sequences of non necessarily consecutive symbols), also of length k. We propose(More)
Even Linear Language class is a subclass of context-free class. In this work we propose a characterization of this class using a relation of nite index. Theorems are provided in order to prove the consistence of the characterization. Finally, we propose a method to learn this class using a reduction to the problem of learning regular languages.
In this paper, we study the notion of k-reversibility and k-testability when regular tree languages are involved. We present an inference algorithm for learning a k-testable tree language that runs in polynomial time with respect to the size of the sample used. We also study the tree language classes in relation to other well known ones, and some properties(More)