Because surveys now can be implemented with relative ease and little cost, many researchers are overlooking the basic principles of survey research. This chapter discusses sources of error that researchers should consider when conducting a survey, and gives readers basic suggestions for reducing error. (Contains 1 table and 1 figure.)

The history of the computer usage in high school laboratories is discussed. Students learned scientific methods by acknowledging measurement errors, using significant digits, questioning their own results, and without doubts, they benefited from applying skill learned in mathematics classes.

This study compares the ability of the multiple indicators, multiple causes (MIMIC) confirmatory factor analysis model to correctly identify cases of differential item functioning (DIF) with more established methods. Although the MIMIC model might have application in identifying DIF for multiple grouping variables, there has been little…

This study examined the effects of controlling the level of difficulty on the sensitivity of repeated curriculum-based measurement (CBM). Participants included 99 students in Grades 2 through 5 who were administered CBM reading passage probes twice weekly over an 11-week period. Two sets of CBM reading progress monitoring materials were compared:…

Eight independent variables (differential item functioning [DIF] detection method, purification procedure, item response model, mean latent trait difference between groups, test length, DIF pattern, magnitude of DIF, and percentage of DIF items) were manipulated, and two dependent variables (Type I error and power) were assessed through…

Unless the sample encompasses a substantial portion of the population, the standard error of an estimator depends on the size of the sample, but not the size of the population. This is a crucial statistical insight that students find very counterintuitive. After trying several ways of convincing students of the validity of this principle, I have…

The concept of a behavior domain is a reasonable and essential foundation for psychometric work based on true score theory, the linear model of common factor analysis, and the nonlinear models of item response theory. Investigators applying these models to test data generally treat the true scores or factors or traits as abstractive psychological…

"Data Trends" reports present summaries of research on mental health services for children and adolescents and their families. The article summarized in this "Data Trends" examines the equivalence of the BPI [Behavior Problem Index] across a sample of African American, Hispanic, and non-Hispanic White children drawn from the…

Multiple-group confirmatory factor analysis was used to investigate factorial invariance between vocational and academic teacher groups on a measure of the learning organization concept. Participants were 488 full-time teachers of public trade industry-technical and business schools located within Seoul, South Korea. Statistically significant…

The various methods for computing the reliability of scores on Advanced Placement (AP) examinations are summarized. For the free response portion of the examinations, raters can contribute to score unreliability through both systematic severity errors (in which some raters consistently rate more severely than other raters) and through…

Data from performance measures that were part of two foreign language teacher certification examinations were used in a generalizability study of the quality of their performance ratings. A total of 775 examinees from the Spanish K-12 and 192 examinees from the French K-12 subject area tests of the Florida Teacher Certification Examinations were…

A reliability analysis was conducted of an abbreviated, 10-item version of the Pupil Control Ideology Form (PCI), using the Cronbach's alpha technique (L. J. Cronbach, 1951) and the computation of the standard error of measurement. The PCI measures a teacher's orientation toward pupil control. Subjects were 168 preservice teachers from one private…

Most training programs in education and psychology focus on classical test theory techniques for assessing score dependability. This paper discusses generalizability theory and explores its concepts using a small heuristic data set. Generalizability theory subsumes and extends classical test score theory. It is able to estimate the magnitude of…

A problem that arises when a differential item functioning (DIF) study is done with samples of examinees differing in ability is examined. A test may function differently when the populations from which the items are calibrated are not of equal ability. Since the lower ability examinees get many difficult items incorrect, the spread (standard…

Standard errors and bias of unidimensional and multidimensional ability estimates were compared in a factorial, simulation design with two item response theory (IRT) approaches, two levels of test correlation (0.42 and 0.63), two sample sizes (500 and 1,000), and a hierarchical test content structure. Bias and standard errors of subtest scores…