proposed a structure-based password attack model, probabilistic context-free grammar (PCFG), that learns the structure distribution of the password from the training set, and describes this distribution in the form of probability.
* A targeted password attacking model: We synthesize the advantages of PCFG and Markov chain models, and propose a targeted password attacking model based on structure partition and string reorganization, which is denoted as TG-SPSR: the basic structure of password is divided into different segments using PCFG algorithm.
Fitch views PCFG
's aforementioned reduction on wholesale funding reliance positively under our baseline assumption that PCF Bank will continue to successfully grow deposits and customers so as to improve the quality and cost of its funding.
Dell'Amico and Filippone  detail a Monte Carlo sampling method that converts a password pw probability as computed by PCFG
or Markov model into an estimate of cracker's guess number:
Szymanski, "Utilizing PCFGs
for modeling and learning service compositions in sensor networks," in Proceedings of the IEEE 9th International Conference on Services Computing (SCC '12), pp.
We have used a Stanford parser which is a java implementation of probabilistic natural language parsers, namely lexicalized dependency parser and lexicalized PCFG
Interface Simbolo no grafica Formalismo Tipo de parser Donatus no NLTK CFG recursivo-descendente RD sim shift-reduce SR sim tabular estrategia TD sim descendente estrategia BU sim ascendente Earley EP nao PCFG
Viterbi VP nao FCFG tabular baseado em tracos FG nao Gramatica projective dependency DG nao Dependencia!
Authors of PCFG
rating indicate at least 60 characteristics that were taken into account for each company in order to obtain appropriate picture of company's corporate governance level.
The phase execution frequencies are provided in the PCFG
Suppose that we do want to use a PCFG
as our statistical parsing mechanism and that, as we said earlier, we have a tree bank.
With the development of tree banks, large databases of sentences annotated with syntactic parse trees (Marcus, Santorini, and Marcinkiewicz 1993b), came an increasing body of research on empirical parsing methods, for example, probabilistic context-free grammars (PCFGs
) (Charniak 1996; Collins 1996; Pereira and Shabes 1992; Lari and Young 1990b).
A considerable body of work is based on probabilistic context-free grammars (PCFGs
), a generalization of context-free grammars that assigns probabilities to each rewrite rule (Lari and Young 199 1; Jelinek, Lafferty, and Mercer 1990).