Concept mapping as a form of student assessment and instruction in the domain of bioengineering

Journal of Engineering Education, Apr 2003 by Walker, Joan M T, King, Paul H

ABSTRACT

This paper describes two pilot studies investigating the use of concept mapping for assessing students' conceptual knowledge at a given point and over time. In Study 1, three groups constructed concept maps in response to the question, "What are the 10-20 most important concepts in biomedical engineering and how are they related?" Group differences were consistent with expert-novice distinctions in structural knowledge: faculty generated dense networks of higher-order principles and their applications while students generated fewer connections among concepts pertaining largely to domain content. Study 2 assessed students' conceptual understanding of the biomedical engineering design process in a yearlong design course at three different time points. Later maps contained a greater number of concepts, more precise vocabulary, and were more valid. These findings are discussed in terms of their implications for theories about the structure of knowledge and identification of the skills associated with a culture of practice.

I. INTRODUCTION

Bioengineering (BE) courses typically adopt traditional approaches to student assessment such as asking students to answer fact-based questions and derive correct solutions. While valuable for tapping forms of knowledge labeled by cognitive psychologists as declarative (i.e., knowing what) and procedural (i.e., knowing how) [1], these forms of assessment often fail to tap a third and vital asset in problem-solving, conditional knowledge (i.e., knowing why and when). Addressing gaps between traditional forms of problem-solving and assessment in the classroom and the day-to-day demands of the workplace, the Vanderbilt-Northwestern-Texas-Harvard/MIT Engineering Research Center (VaNTH ERC) is investigating alternative and more comprehensive methods for capturing and assessing what students know, and developing tools that help students integrate an array of diverse competencies across the be curriculum. One potentially useful tool for achieving these goals is concept mapping.

Invented during the 1970s by Novak and his colleagues at Cornell University, a concept map looks like a flow chart. However, instead of "mapping the linear or logical structure of knowledge, concept maps reflect the psychological structure of knowledge [2]." Theoretically, knowledge functions as a semantic network [3]. Thus, learning is not only the acquisition and understanding of concepts but also the construction of meaningful links among concepts [4]. Consistent with these theoretical perspectives, concept maps are composed of interrelated elements: nodes, directed lines and labels. Nodes represent concepts. Concepts are defined as "perceived regularities in events or objects, or records of events or objects, designated by a label [5]." For example, "engineering" and "experimentation" are concepts. Lines represent relations among concepts. Labels in the lines describe the nature of those relations (e.g., "leads to") while arrowheads indicate the direction of the relationship. The combination of a pair of concepts and a line constitutes the fundamental unit of a concept map, a proposition. Each proposition, or unit of psychological meaning, is a statement "about some object or event in the universe, either naturally occurring or constructed [5]" (e.g., "engineering leads to experimentation"). Figures 1 and 2 provide examples of how concept maps can be structured hierarchically and non-hierarchically, and describe aspects of concept mapping.

Concept maps can be used as a learning strategy, an instructional strategy, a strategy for curriculum planning, and a means of student assessment [6]. Use of concept mapping has been associated with the enhancement of numerous student outcomes, including greater focus on salient rather than irrelevant aspects of the problem to be solved [7], transfer of problem-solving skills [8], and better test scores [9, 10]. The technique may have these effects because it facilitates the achievement of a shared conceptual understanding between teacher and student. Unlike traditional forms of assessment (e.g., multiple-choice tests), concept mapping allows teachers the opportunity to observe how extensive and integrated a student's conceptual knowledge is, and, in turn, share their own conceptual understanding with students. Given that students enter the classroom with diverse experiences and levels of prior knowledge, it is often difficult for teachers to know what students do and do not understand. Moreover, concept mapping as a form of assessment offers teachers the opportunity to recognize a student's misconceptions, impediments to learning that traditional assessments may not detect.

Fundamentally, "the more concepts to which a given concept is linked, the better defined or explicated that concept is [11]." Put another way, the more dense the network, the deeper the understanding. Supporting this argument is evidence that, given identical problems, novices and experts structure their knowledge quite differently [12]. Experts tend to display "conceptually rich tapestries of interrelated ideas" while novices tend to possess undifferentiated, incomplete, and sometimes erroneous knowledge structures [13]. Further, experts appear to make efficient use of their dense networks while novices tend to represent their thinking in disorganized arrays [14].