Measurement in Education in the United States
Authors: Cizek Gregory , Agger Charlotte , Lim Slki 
Published: June 2013

Educational measurement is the science and practice of obtaining information about characteristics of students, such as their knowledge, skills, abilities, and interests. Measurement in education includes the development of instruments or protocols for obtaining information, procedures for analyzing and evaluating the quality of that information, and strategies for communicating the information to audiences, such as educators, policymakers, parents, and students. All measurement in education has the common aims of (1) arriving at defensible conclusions regarding students’ ability, achievement, or interests, (2) gauging student progress toward specified educational goals, and (3) improving teaching and learning. Educational measurement is closely related to the concepts of testing, assessment, and evaluation. Measurement is the process of assigning numbers to events based on an established set of rules. In educational measurement, the “events” under consideration are students’ test performances and, in the simplest case, the numerals assigned might be the students’ numbers of correct responses. An example of a set of “rules” in this situation would be that one point is earned for each correct response, zero points are earned for an incorrect response, and the sum of these values is the student’s total test score. Percentage correct is another commonly used metric, although a variety of transformations of raw scores may be used. Testing uses measurement to support inferences about students’ knowledge, skills, or abilities. A test is any systematic sample of behavior obtained under controlled conditions. In educational measurement, the behaviors of interest would encompass, for example, mathematics problem solving, interest in various occupations, proficiency in reading narrative texts, skill in giving a speech, building a birdhouse, writing an essay, and so on. Because it is not possible to observe all of what a student knows or can do, educational measurement is based on samples of these behaviors. Consequently, when a test is administered, inference is always required. Because it is typically not the student’s performance on the specific math problems or on the specific essay that is of interest, those behaviors are considered to be samples of the student’s underlying problem-solving skill or writing ability. Inference is an informed conclusion, based on the sample of behavior, about the student’s more fundamental level of knowledge or skill. In educational testing, the conditions of testing are controlled so that inferences about differences in students’ knowledge, skill, or ability can be confidently attributed to the underlying characteristics being measured and not to variation in testing conditions. Evaluation is ascribing value or worth to the information collected via measurement or testing. A common form of educational evaluation is grading, where a value label (such as “Pass,” “Fail,” or “A”) is used to connote information about the merit of the student’s performance. Finally, assessment refers to the process of gathering and synthesizing information from multiple sources—some or all of which may be tests—for the purposes of discovering and documenting students’ strengths and weaknesses, planning and enhancing instruction, or evaluating and making decisions about students.