Blocking between landmarks during 2-D (touchscreen) and 3-D (ARENA) search tasks with pigeons

Many studies investigating cue competition have focused on the blocking effect. We investigated the blocking effect with pigeons using a landmark-based spatial search task in both a touchscreen preparation (Exp. 1a) and an automated remote environmental navigation apparatus (Exp. 1b). In Phase 1, two landmarks (LMs: A and Z) appeared on separate trials as colored circles among a row of eight (touchscreen) or six (ARENA) identical response units. Subjects were rewarded for pecking at a target response unit to the right of LM A and to the left of an extraneous LM, Z. During the blocking trials in Phase 2, LM X was presented in compound with a second LM (A) that had been previously trained. On control trials, LM Y was presented in compound with LM B and a target in the same manner as in the trials of AX, except that neither landmark had previously been trained with the target. All subjects were then tested with separate trials of A, X, B, and Y. Testing revealed poor spatial control by X relative to A and Y. We report the first evidence for a spatial-blocking effect in pigeons and additional support for associative effects (e.g., blocking) occurring under similar conditions (e.g., training sessions, spatial relationships, etc.) in 3-D and 2-D search tasks.     

Design of minimum sensitivity multiple loop feedback bandpass active filters

A method is described for determining multiple loop feedback topologies which yield minimum sensitivities for symmetrical, all-pole bandpass filters. The procedure begins with a follow-the-leader feedback (FLF) topology and additional feedback loops are constructed until minimum sensitivity is achieved. Filters comprised of identical second-order sections and non-identical sections, respectively, are considered.     

Relationship of Physique and Developmental Level to Physical Performance

Abstract

A study was made of the relationship of physique and developmental level, determined by use of the Wetzel Grid, to performance of junior high boys on four fitness tests: pull-ups, 50-yd. dash, standing broad jump, and softball throw. Subjects of different physique groups (heavy, medium, and thin) who were alike developmentally (accelerated, normal, and retarded) differed more markedly in performance than did subjects of different developmental levels who were alike with regard to physique. Subjects who were medium in physique and normal in development were the best performers. Subjects of heavy physique (many overweight) were the poorest performers. This would seem to indicate the need for a restudy of classification methods, particularly when norms are to be used for evaluating performance.     

Sample design for international studies of educational achievement

Author of numerous publications on the use of social indicators to guide decisions concerning resource allocation within education systems. Co-editor of Planning the Quality of Education (IIEP-UNESCO and Pergamon Press). His research interests are focused on indicators of the quality of basic education in developing countries.     

An economic evaluation of elementary education for dropouts in Indonesia

The article presents the results of benefit-cost analysis for an experimental and prototype elementary education program in Indonesia which is designed to solve a serious dropout problem. The program will use nonformal and self-paced methods to return 10, 000 children to elementary school in order to complete grades four through six.Alternative benefit-cost ratios are calculated using differing assumptions regarding probable lifetime earnings-enhancement and alternative discount rates. The calculations consider only private benefits and opportunity costs in addition to the project budget; however, several of the problems and unresolved questions that arose in the process of making the evaluation in a less developed country are discussed.     

Use of Standardized Tests in Teacher Evaluation for Career Ladder Systems

In most current teacher evaluation systems, tests are typically used for all teachers or for none. Peterson describes how three Utah school districts employed tests, specifically National Teachers Examinations, as one line of optional evidence for use along with a selection of other evidence in the promotion of eligible teachers. The author indicates that the optional use of test scores both answers many objections to the testing of veteran teachers and allows the test results of teachers choosing to submit them to inform promotion decisions.