tailieunhanh - TAL - A National Database of Questions - Classification is the Key

We will refer to embeddings providing a guarantee akin to that of Lemma as JL- embeddings. In the last few years, such embeddings have been used in solving a variety of problems. The idea is as follows. By providing a low-dimensional representation of the data, JL-embeddings speed up certain algorithms dramatically, in particular algorithms whose run-time depends exponentially in the dimension of the working space. (For a number of practical problems the best-known algorithms indeed have such behavior.) At the same time, the provided guarantee regarding pairwise distances often allows one to establish that the solution found by working in the low-dimensional space is a good. | Maths-CAA Series May 2003 TAL - A National Database of Questions -Classification is the Key Contents Introduction 2 Motivation for Creating TAL 3 Why do we use questions 3 An Automated Test Generator 5 An Approach to Classification 7 Practical classification problems 8 A General Classification Scheme 12 The Mathematics Subject Scheme 12 How to specify a question slot 14 Conclusions 15 Appendix A 15 Appendix B 16 References 17 1 TAL - A National Database of Questions -Classification is the Key Jon Sims Williams and Mike Barry Dept Engineering Maths Bristol University Email Abstract This paper discusses a CAAsystem called TAL. TAL is unusual in that it allows users to generate large numbers of equivalent tests from a specification. The tests are generated from a database of questions and all questions must be classified. Some of the difficulties involved in classifying questions are discussed. 1. Introduction The Test and Learn system TAL is a database of questions with facilities for staff to set tests and students to take tests. It was first conceived in 1994. We built a system which allowed students to run a programme on their PC linked to a remote computer. The system collected a test from the remote computer ran the test locally on the PC and then sent the results back to the host computer. The system used the basic systems of computer-to-computer direct links that were available at that time and worked very reliably. A bid to JISC was successful Higher Education Funding Committee JISC Technology Applications Project 2 352 in 1996. With this support we built a web-based version that was first used in 1997. The task of populating the database with a large enough set of questions was perceived to be too onerous a task for one university or department and so the system was built to allow several universities to use the same set of questions in the hope that participating staff would gradually add to the database