Unique-order interpolative coding for fast querying and space-efficient indexing in information retrieval systems

This paper presents a size reduction method for the inverted file, the most suitable indexing structure for an information retrieval system (IRS). We notice that in an inverted file the document identifiers for a given word are usually clustered. While this clustering property can be used in reducing the size of the inverted file, good compression as well as fast decompression must both be available. In this paper, we present a method that can facilitate coding and decoding processes for interpolative coding using recursion elimination and loop unwinding. We call this method the unique-order interpolative coding. It can calculate the lower and upper bounds of every document identifier for a binary code without using a recursive process, hence the decompression time can be greatly reduced. Moreover, it also can exploit document identifier clustering to compress the inverted file efficiently. Compared with the other well-known compression methods, our method provides fast decoding speed and excellent compression. This method can also be used to support a self-indexing strategy. Therefore our research work in this paper provides a feasible way to build a fast and space-economical IRS.     

What do freshmen really know about research? Assess before you teach

The paper describes an effort to assess the information literacy skills of first year college students. An instrument was developed and information was gathered on students' experience and comfort in conducting library research as well as their perceived competence with specific information literacy skills. In addition, students completed a skills test to assess specific knowledge and skills relating to information literacy. Entering freshmen generally self-reported their skills to be less than “excellent.” This finding was supported by the results of the skills test. Strengths and weaknesses in information literacy skills are reported as well as implications for librarians who assess and teach these skills to students.     

A medical journal's beta site: experimentation at NEJM

When continuous development becomes the norm on the social web, finding a way to put forward new development ideas to your audience and get their feedback at an early stage is the natural result. This article discusses how one major medical journal created a ‘beta’ site to support new online development and gather user feedback, speeding development initiatives and creating intrinsic value in the experimental environment. The goals of the site, organization of the teams, and practical and brand benefits are discussed.     

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Index to Volume XLI