Ayako Hoshino

A Real-Time Multiple-Choice Question Generation For Language Testing: A Preliminary Study

An automatic generation of multiple-choice questions is one of the promising examples of educational applications of NLP techniques. A machine learning approach seems to be useful for this purpose because some of the processes can be done by classification. Using basic machine learning algorithms as Naive Bayes and K-Nearest Neighbors, we have developed a real-time system which generates questions on English grammar and vocabulary from on-line news articles. This paper describes the current version of our system and discusses some of the issues on constructing this kind of system.

A cloze test authoring system and its automation

This paper presents a pilot system and discusses its possible extensions. In the first sections, we present a web-based test authoring system for English grammar and vocabulary. It assists language teachers to make questions on arbitrary input texts, such as online news. The system employs the techniques of NLP (Natural Language Processing) and is compared with other studies in the same field. In the latter sections we discuss some extensions of the system. First, we show a method of automatically acquiring the grammar targets. Secondly, we discuss an extension to a computer-adaptive question generator which interacts with students. We describe the design of the extended system and focus on the difficulty predictor, one of the major components needed. Then we present some primary results of the difficulty prediction task. Finally, we compare existing systems and discuss their use and evaluations.

New polyhydroxylated sterols stylisterols A-C and a novel 5, 19-cyclosterol hatomasterol from the okinawan marine sponge Stylissa sp.

New polyhydroxylated sterols, stylisterol A-C (1-3), and a novel 5,19-cyclosterol, hatomasterol (4) were isolated from the Okinawan sponge Stylissa sp. Structural determinations of these compounds were made by spectroscopic analysis and chemical conversion. Assessment of cytotoxicity toward HeLa cells was also determined.

WebExperimenter for Multiple-Choice Question Generation

Automatic generation of multiple-choice questions is an emerging topic in application of natural language processing. Particularly, applying it to language testing has been proved to be useful (Sumita et al., 2005).

Amitorines A and B, Nitrogenous Diterpene Metabolites of Theonella swinhoei: Isolation, Structure Elucidation, and Asymmetric Synthesis

Two new nitrogenous prenylbisabolanes never before found in Lithistid sponges have been isolated from Theonella swinhoei. These new diterpenes, named amitorine A (1) and amitorine B (2), containing a prenylbisabolane skeleton have been characterized by spectroscopic analyses, and the relative and absolute configurations of 1 and 2 were determined by asymmetric synthesis of both diastereomers via the common bicyclic lactone 6 intermediate.