Development and Validation of the Light and Spectroscopy Concept Inventory

Abstract

This article describes the development and validation of the Light and Spectroscopy Concept Inventory (LSCI), a 26-item diagnostic test designed (1) to measure students' conceptual understanding of topics related to light and spectroscopy, and (2) to evaluate the effectiveness of instructional interventions in promoting meaningful learning gains in an introductory college astronomy course. We also present the final field-tested version of the LSCI for general use by the astronomy education community. Process of test construction:1. Identify the primary purpose for which test scores will be used. 2. Define the concept domain to be addressed by the test. 3. Construct and review an initial pool of items. 4. Hold preliminary item tryouts and revise as necessary. 5. Field-test items with a large sample representative of the population for whom the test is intended. 6. Determine statistical properties of item scores and, when appropriate, eliminate items that do not meet pre-established criteria. 7. Conduct reliability and validity studies for the final form of the test. PURPOSE AND SPECIFICATIONSAs discussed in our previous paper (Bardar (Weeks) et al. 2005), the purpose of developing a Light and Spectroscopy Concept Inventory for the introductory college astronomy survey course was twofold: (1) to produce a standardized assessment instrument for evaluating individual students' conceptual understanding of topics central to the course, and (2) to produce a tool for evaluating and comparing the relative effectiveness of various instructional methods in promoting conceptual change.Through an extensive review of journal articles and surveys of faculty, syllabi, and textbooks, we came to the conclusion that the electromagnetic spectrum and the nature of light are widely acknowledged within the astronomy education community as the most taught and most important topics in introductory astronomy courses (Slater & Adams 2003;Slater et al. 2001;Zeilik & Morris-Dueer 2005) and as topics with which students struggle (Brecher 1991;Zeilik, Schau, & Mattern 1998). These topics therefore present themselves as a natural choice for a central theme around which to develop a concept inventory that would allow astronomy instructors to compare the success of the teaching and learning that takes place in the widest possible range of introductory courses.The concept domain of the LSCI, shown below, was chosen to reflect the most commonly taught concepts addressed by the majority of courses within the astronomical community. Concepts addressed by the LSCI:The nature of the electromagnetic spectrum, including the interrelationships of wavelength, frequency, energy, and speed Interpretation of Doppler shift as an indication of motion rather than color of an object The correlation between peak wavelength and temperature of a blackbody radiator Relationships between luminosity, temperature, and surface area of a blackbody radiator The connection between spectral features and underlying physical processes ITEM DEVELOPMENTTo minimize the time and e...

Analysis of the Astronomy Diagnostic Test

“…However, this is a double-edged sword. Concept inventories that focus on a single conceptual domain, like the ones on lunar phases (Lindell 2001), stars (Bailey 2006), greenhouse effect (Keller 2006), and light and spectra (Bardar 2006;Bardar et al 2007), probe conceptual understanding of one particular topic and may be more sensitive to different instructional designs. For concept inventories to be successful, it is important that they are developed by people who are also experts in the discipline, as Hake (2007) argued.…”

Applicability of the Newtonian gravity concept inventory to introductory college physics classes

“…Pre-and post-instructional testing with concept inventories have become a common method for assessing physics and astronomy teaching and learning on a large scale, leading to profound insights and evidence for the success of curriculum reform. [6][7][8][9][10][11][12][13] In this paper, we build on this literature and provide a new tool for assessing changes in introductory algebra-based students' conceptual understandings and reasoning about gravity-the Newtonian Gravity Concept Inventory (NGCI).…”

Student Understanding of Blackbody Radiation and Its Application to Everyday Objects

“…It is often taught together with other fundamental experiments such as the photoelectric effect, Compton scattering, and the Bohr model in order to motivate the necessity for quantization. Some previous research has been conducted on student understanding of these topics, but very little on blackbody radiation [1][2][3]. These other experiments draw on ideas that are familiar to students from introductory courses (electric circuits, momentum conservation, and atomic structure), while blackbody radiation is arguably more abstract.…”