ERIC Number: ED406225
Record Type: RIE
Publication Date: 1997-Mar
Estimating Numerosity in a Rectangular Grid: The Development of a Clever Estimation Strategy.
De Corte, Erik; And Others
This study investigates the development of an adaptive strategy for estimating numerosity from the theoretical perspective of strategic change. A simple estimation task was used. Participants of 3 different age groups (20 university students, 20 sixth-graders and 10 second-graders) had to estimate 100 numerosities of colored blocks presented in a 10 X 10 rectangular grid. This task allows for two distinct estimation procedures: (1) repeatedly adding estimations of groups of blocks (= addition procedure); or (2) subtracting the estimated number of empty squares from the (estimated) total number of squares in the grid (= subtraction procedure). A rational task analysis indicates that the most efficient overall estimation strategy consists of adaptive use of both procedures, depending on the ratio of blocks to empty squares. The first hypothesis was that there would be a developmental difference in the adaptive use of the two procedures. According to the second hypothesis, this adaptive use will result in better estimation accuracy. Converging evidence from different kinds of data (i.e., response times, error rates, and retrospective reports) supported both hypotheses. Contains 22 references. (Author/PVD)
Descriptors: Cognitive Development, Cognitive Psychology, Cognitive Style, College Students, Computation, Constructivism (Learning), Discovery Processes, Elementary Education, Estimation (Mathematics), Grade 2, Grade 6, Higher Education, Learning Strategies, Numeracy, Strategic Planning, Thinking Skills
Publication Type: Reports - Research; Speeches/Meeting Papers
Education Level: N/A
Authoring Institution: N/A
Grant or Contract Numbers: N/A
Note: Paper presented at the Annual Meeting of the American Educational Research Association (Chicago, IL, March 24-28, 1997).