The aim of this dissertation is to study statistical methods for multilingual word segmentation and POS tagging with high accuracy. Word segmentation and part-of-speech (POS) tagging are fundamental language analysis tasks in natural language processing, and used in many applications. Existence of unknown words is a large problem in these tasks and they need to be properly handled. We attempt t...

A source sequence is to be guessed with some fidelity based on a rate-limited description of an observed which it correlated. The tension between the rate and exponential growth power mean required number guesses quantified. This can viewed as guessing version classical indirect-rate-distortion problem Dobrushin-Tsybakov’62 Witsenhausen’80. Judicious choices correlated sequence, r...

The increased availability of time-related information as a result computer-based assessment has enabled new ways to measure test-taking engagement. One these is distinguish between solution and rapid guessing behavior. Prior research recommended response-level filtering deal with guessing. Response-level can lead parameter bias if depends on the measured trait or (un-)observed covariates. Ther...

For a given number of colors, $s$, the guessing graph is (base $s$) logarithm cardinality largest family colorings vertex set such that color each can be determined from colors vertices in its neighborhood. This quantity related to problems network coding, circuit complexity and entropy. We study graphs as property context classic extremal questions, relationship forbidden subgraph property. fi...

We propose a general technique to improve the key-guessing step of several attacks on block ciphers. This is achieved by defining and studying some new properties associated S-boxes representing them as special type decision trees that are crucial for finding fine-grained guessing strategies various attack vectors. have proposed implemented algorithm efficiently finds such trees, use it providi...