In this paper, we report on a series of algebra classes with a group of low-income, African American mothers of elementary-aged children who had limited and negative formal experiences with algebra. We drew from United States reform-oriented elementary mathematics curricular materials in the classes. The women initially arrived to the class out of…

This article describes the construction of a hierarchical taxonomy of metacognitive activities for the interpretation of thinking-aloud protocols of students in secondary education, who studied texts on history and physics. After testing an initial elaborate taxonomy on a restricted number of protocols by multiple raters, it appeared that the…

The authors present 10 experiments that challenge some central assumptions of the dominant theories of visual search. Their results reveal that the complexity (or redundancy) of nontarget items is a crucial but overlooked determinant of search efficiency. The authors offer a new theoretical outline that emphasizes the importance of nontarget…

Mathematical signs and symbols have a decisive role for coding, constructing and communicating mathematical knowledge. Nevertheless these mathematical signs do not already contain mathematical meaning and conceptual ideas themselves. The contribution will present basic elements of an epistemology of mathematical knowledge and then apply these…

This manual was written as part of a study entitled "Studying the Cost and Value of Library Services," conducted from fall 1993 through spring 1995. The goal of the study was to address the problem of developing models and methods for studying the cost and value of library and information services in a way that can be pragmatically…

A previously developed method of automatically selecting items for inclusion in a test subject to constraints on item content and statistical properties is applied to real data. Two tests are first assembled by experts in test construction who normally assemble such tests on a routine basis. Using the same pool of items and constraints articulated…

The Adult Education components of the 1991 and 1995 National Household Education Survey (NHES) collected the name and subject matter of a wide range of courses adults had taken in the previous months. Adult education involves a variety of types of courses, whether related to basic skills, equivalency programs, degree programs, or personal…

The National Household Education Survey (NHES) is a data collection system of the National Center for Education Statistics that is designed to provide information about educational issues best addressed through contacting households rather than institutions. In 1995, as in 1991, one of the components of this telephone survey was a study of adult…

This study is a critical evaluation of the roles for coding and scoring of missing responses to multiple-choice items in educational tests. The focus is on tests in which the test-takers have little or no motivation; in such tests omitting and not reaching (as classified by the currently adopted operational rules) is quite frequent. Data from the…

The cognitive effects of self-referencing in math word problems were studied in 100 third, fourth, and fifth graders solving compare-unknown and referent-unknown problems. In general, self-referencing (referring to "you") facilitated encoding processes in solving these problems. Self-referencing appeared to decrease the load on working…

Investigates how coder characteristics such as language skills, political knowledge, coding experience, and coding certainty affected inter-coder and coder-training reliability. Shows that language skills influenced both reliability types. Suggests that cross-national researchers should pay more attention to cross-national assessments of…

Describes a classroom exercise that uses a letter from Max Delbruck to George Beadle to stimulate interest in the mechanics of a nonoverlapping comma-free code. Enables students to participate in the rich history of molecular biology and illustrates to them that scientists and science can be fun. (JRH)

Discusses problems in using ASCII for data communications and computers and provides a historical perspective on the development of Unicode, a new universal encoding scheme. The future of Unicode is considered, implications for libraries are discussed, and a sidebar explains how computers store textual data. (LRW)

Presents general principles for cleaning data sets. Suggests techniques: check for column shifts, data completeness, marginal frequencies, and selected cross-tabulations; examines a sample of cases. Gives strategies for preventing data processing errors. (SK)

Describes a detailed algorithm for fast text compression. Related to the PPM (prediction by partial matching) method, it simplifies the modeling phase by eliminating the escape mechanism and speeds up coding by using a combination of quasi-arithmetic coding and Rice coding. Details of the use of quasi-arithmetic code tables are given, and their…