An algorithm is given for the addition and subtraction of fractions based on dividing the sum of diagonal numerator and denominator products by the product of the denominators. As an explanation of the teaching method, activities used in teaching are demonstrated. (MN)

Helping teachers to build a strong bridge from concrete experiences to algorithms is the focus. A detailed sequence of activities is described. (MN)

Instructional sequences are presented for teaching two-digit multiplication and division with one- and two-digit divisors using a base-oriented approach. (MN)

A teaching sequence provides a guide to instruction on initial concepts of fractions, equivalent fractions, and addition with fractions. (MN)

How teachers can diagnose difficulties with computation is discussed, with emphasis on how to develop diagnostic tests. How to use such tests to plan remediation is considered in terms of several types of errors. (MN)

The authors attempt to determine the effects of the use of direct and "combinations of tens" methods of two column-addition, ability, and grade level as factors in column addition efficiency. (MN)

This is a special issue examining the potential of cybernetics in educational technology. Articles discuss: cybernetic methods, algorithms, feedback learning theory, a structural approach to behavioral objectives and criterion-referenced testing, task specifications and diagnosis, teacher-child interaction, educational development, teaching…

Provides a metric area model which may be used to explain the square root algorithm. (CP)

The author mentions several broad types of student elementary algebra errors, including incorrect cancellation and cross-multiplication, notes confusing terms and factors, and gives several suggestions to help students avoid these. (MN)

Proposes a criterion for selecting a sequence of objectives from a learning hierarchy and describes a sequence generating algorithm which is designed to generate a minimal memory load sequence from a learning tree. Its effectiveness in generating low memory load sequences from hierarchies that are not trees is also discussed. (RP)

Seven data sets (namely, clinical data on children) were subjected to clustering by seven algorithms--the B-coefficient, Linear Typal Analysis; elementary linkage analysis, Numerical Taxonomy System, Statistical Analysis System hierarchical clustering method, Taxonomy, and Bolz's Type Analysis. The little-known B-coefficient method compared…

Describes and discusses the findings of an experiment that tested the precision of full-text retrieval enhanced by 29 document term weighting algorithms at the lowest, middle, and highest levels of recall, and compared with the precision of full-text retrieval without algorithms and with paragraph retrieval. (29 references) (Author/CLB)

Discussion of a new method of index term dictionary compression in an inverted-file-oriented database highlights a technique of word coding, which generates short fixed-length codes obtained from the index terms themselves by analysis of monogram and bigram statistical distributions. Substantial savings in communication channel utilization are…

Sixteen Brazilian third graders aged 8-13 were given problems involving multidigit computation. School-taught algorithms were likely to be used in school-taught problems, with little carry-over to real problem situations, but resulted in more incorrect answers. (MNS)

The Hepatitis Knowledge Base (text of prototype information system) was used for modifying and testing "A Navigator of Natural Language Organized (Textual) Data" (ANNOD), a retrieval system which combines probabilistic, linguistic, and empirical means to rank individual paragraphs of full text for similarity to natural language queries…