We present a framework facilitating the implementation and comparison of text compression algorithms. We evaluate its features by a case study on two novel compression algorithms based on the Lempel-Ziv compression schemes that perform well on highly repetitive texts.

Neutrality is important in natural, molecular and artificial evolution. This work studies how local neutral degree varies over the genospace in a simple class of Lindenmayer-systems, and investigates whether this variation relates to Lempel-Ziv complexity of the phenotype.

In this paper we give an infinite family of strings for which the length of the Lempel-Ziv’77 parse is a factor Ω(log n/ log log n) smaller than the smallest run-length grammar.

We present an algorithm that computes the Lempel-Ziv decomposition in O(n(log σ+log log n)) time and n log σ+ǫn bits of space, where ǫ is a constant rational parameter, n is the length of the input string, and σ is the alphabet size. The n log σ bits in the space bound are for the input string itself which is treated as read-only.

On the complexity of master problems Emergence on decreasing sandpile models 14:35 Kosolobov Durand, Romashchenko Faster lightweight Lempel-Ziv parsing Quasiperiodicity and non-computability in tilings On the Complexity of Noncommutative Polynomial Factorization

While entropy per unit time is a meaningful index to quantify the dynamic features of experimental time series, its estimation is often hampered in practice by the finite length of the data. We here investigate the performance of entropy estimation procedures, relying either on block entropies or Lempel-Ziv complexity, when only very short symbolic sequences are available. Heuristic analytical ...

The pressing need for efficient compression schemes for XML documents has recently been focused on stack computation [6, 9], and in particular calls for a formulation of information-lossless stack or pushdown compressors that allows a formal analysis of their performance and a more ambitious use of the stack in XML compression, where so far it is mainly connected to parsing mechanisms. In this ...

Wojciech Szpankowski'" Department of Computer Science Purdue University W. Lafayette, IN 47907 U.S.A. It was conjectured that the average redundancy rate, Tnl for the Lempel-Ziv code (LZ78) is 0(loglognflogn) where n is the length of the database sequence. However, it was also known that for infinitely many n the redundancy Tn is bounded from the below by 2/ log n. In this paper we settle the a...