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This paper describes the development of a genetic algorithm (GA) for the assignment of weights to query terms in a ranked‐output document retrieval system. The GA involves a fitness function that is based on full relevance information, and the rankings resulting from the use of these weights are compared with the Robertson‐Sparck Jones F4 retrospective relevance weight. Extended experiments with seven document test collections show that the ga can often find weights that are slightly superior to those produced by the deterministic weighting scheme. That said, there are many cases where the two approaches give the same results, and a few cases where the F4 weights are superior to the ga weights. Since the ga has been designed to identify weights yielding the best possible level of retrospective performance, these results indicate that the F4 weights provide an excellent and practicable alternative. Evidence is presented to suggest that negative weights may play an important role in retrospective relevance weighting.

This paper provides an introduction to the use of n‐grams in textual information systems, where an n‐gram is a string of n, usually adjacent, characters extracted from a section of continuous text. Applications that can be implemented efficiently and effectively using sets of n‐grams include spelling error detection and correction, query expansion, information retrieval with serial, inverted and signature files, dictionary look‐up, text compression, and language identification.

This paper provides an introduction to genetic algorithms, a new approach to the investigation of computationally‐intensive problems that may be insoluble using conventional, deterministic approaches. A genetic algorithm takes an initial set of possible starting solutions and then iteratively improves these solutions using operators that are analogous to those involved in Darwinian evolution. The approach is illustrated by reference to several problems in information retrieval.

This paper describes the design of a stemming algorithm for searching databases of Latin text. The algorithm uses a simple longest‐match approach with some recoding but differs from most stemmers in its use of two separate suffix dictionaries (one for nouns and adjectives and one for verbs) for processing query and database words. These dictionaries and the associated stemming rules are arranged in such a way that the stemmer does not need to know the grammatical category of the word that is being stemmed. It is very easy to overstem in Latin: the stemmer developed here tends, rather, towards understemming, leaving sufficient grammatical information attached to the stems resulting from its use to enable users to pursue very specific searches for single grammatical forms of individual words.

Genetic algorithms are a class of non‐deterministic algorithms that derive from Darwinian evolution and that provide good, though not necessarily optimal, solutions to combinatorial problems. We describe their application to the identification of characteristics that occur approximately equifrequently in a database, using two different methods for the creation of the chromosome data structures that lie at the heart of a genetic algorithm. Experiments with files of English and Turkish text suggest that the genetic algorithm developed here can produce results superior to those produced by existing non‐deterministic algorithms; however, the results are inferior to those produced by an existing deterministic algorithm.

To reexamine the Weber Thesis pertaining to the relationship between ascetic Protestantism – especially Calvinism – and modern capitalism, as between an economic “spirit” and an economic “structure,” in which the first is assumed to be the explanatory factor and the second the dependent variable.

The chapter provides an attempt to combine theoretical-empirical and comparative-historical approaches to integrate theory with evidence supplied by societal comparisons and historically specific cases.

The chapter identifies the general sociological core of the Weber Thesis as a classic endeavor in economic sociology (and thus substantive sociological theory) and separates it from its particular historical dimension in the form of an empirical generalization from history. I argue that such a distinction helps to better understand the puzzling double “fate” of the Weber Thesis in social science, its status of a model in economic sociology and substantive sociological theory, on the one hand, and its frequent rejection in history and historical economics, on the other. The sociological core of the Thesis, postulating that religion, ideology, and culture generally deeply impact economy, has proved to be more valid, enduring, and even paradigmatic, as in economic sociology, than its historical component establishing a special causal linkage between Calvinism and other types of ascetic Protestantism and the “spirit” and “structure” of modern capitalism in Western society at a specific point in history.

In addition to the two cases deviating from the Weber Thesis considered here, it is necessary to investigate and identify the validity of the Thesis with regard to concrete historical and empirical instances.

The chapter provides the first effort to systematically analyze and distinguish between the sociological core and the historical components of the Weber Thesis as distinct yet intertwined components.

Purpose: To describe how an approach to instruction that intentionally considers elements of motivation and engagement, intensity of instruction, and cognitive challenge can accelerate the reading achievement of lower-performing readers by giving them access to and support to meet reading and knowledge building with success.

Design: The authors discuss a set of high-leverage practices squarely under the teacher’s control. Grounded in longstanding and rigorous research, the integrated set of practices have been shown time and time again to accelerate achievement beyond typical growth while also intentionally considering the experiences, cultures, and linguistic knowledge students bring to the classroom. The re-conceptualized approach forefronts student agency and engages students in meaningful interactions with text to build knowledge of the world they live in.

Findings: The authors illustrate the comprehensive approach through a composite vignette drawn from work with teachers and students in school and clinical contexts. The focus of the vignette is on the actions of the classroom teacher who is working to meet the needs of three struggling readers within the broader context of her 5th-grade classroom, while also establishing a coherent instructional approach with fellow teachers.

Practical Implications: By re-conceptualizing their approaches to working with struggling readers, teachers increase the likelihood that students will not only develop component skills related to reading but also integrate these components and develop the conceptual expertise that anchors future reading and learning.

This chapter attempts to untangle the complex arena of private sector engagement in education by discussing the definitional challenges associated with understanding the non-state sector and by introducing some conceptual frameworks employed in research on private education. A thematic review of research from the field of Comparative International Education is provided to give the reader an understanding of the diversity that characterizes private involvement as well as the interconnectedness of private actors, specifically drawing attention to findings that grapple with equity implications. The chapter concludes with some suggestions for developing a framework for research via posing questions that ought to be asked when designing, conducting and analyzing findings from studies into private sector engagement in education.