Cengiz Zopluoglu

University of Oregon | UO · Department of Educational Methodology, Policy &Leadership

A mixture extension of Samejima’s Continuous Response Model for continuous measurement outcomes and its estimation through a heuristic approach based on limited-information factor analysis is introduced. Using an empirical dataset, it is shown that two groups of respondents that differ both qualitatively and quantitatively in their response behavio...

Researchers frequently use machine-learning methods in many fields. In the area of detecting fraud in testing, there have been relatively few studies that have used these methods to identify potential testing fraud. In this study, a technical review of a recently developed state-of-the-art algorithm, Extreme Gradient Boosting (XGBoost), is provided...

Response time (RT) information has recently attracted a significant amount of attention in the literature as it may provide meaningful information about item preknowledge. In this study, a Deterministic Gated Lognormal Response Time (DG-LNRT) model is proposed to identify examinees with potential item preknowledge using RT information. The proposed...

Response time information has recently attracted significant attention in the literature as it may provide meaningful information about item preknowledge. The methods that use response time information to identify examinees with potential item preknowledge make an implicit assumption that the examinees with item preknowledge differ in their respons...

Language proficiency assessments are pivotal in educational and professional decision-making. With the integration of AI-driven technologies, these assessments can more frequently use item types, such as dictation tasks, producing response features with a mixture of discrete and continuous distributions. This study evaluates novel measurement model...

Research in psychology, sociology, economics, and other disciplines investigating social justice has identified associations between fair treatment and human well-being. However, the lack of a practical and valid instrument for measuring individual experiences of fair treatment in multiple areas of life has limited the ability to understand the rel...

This mixed methods study describes the development and initial validation of the Culture of Belonging (CoB) Barometer. The instrument measures how university students experience belonging in their interactions with faculty, staff, administrators, and other students. Instrument development methods included focus groups, a pilot survey, and stakehol...

Unfolding models, also referred to as ideal point models, are typically used to measure attitudes, preferences, and personality. Available computer packages for fitting unfolding models are very limited compared with a wide selection of computer programs for fitting other item response theory models. This impedes the methodological development of u...

Response times (RTs) have recently attracted a significant amount of attention in the literature as they may provide meaningful information about item preknowledge. In this study, a new model, the Deterministic Gated Lognormal Response Time (DG‐LNRT) model, is proposed to identify examinees with item preknowledge using RTs. The proposed model was a...

Mattering is defined as experiences of feeling valued and adding value in different domains of life: self, relationships, work, and community. Mattering is a construct with great relevance across psychological and social issues. Research has suggested there may be value in understanding group differences in mattering. Following the recent validatio...

Pragmatic instruments with psychometric support are important to advance dissemination and implementation (D&I) research, but few well-researched D&I instruments exist. Item response theory (IRT), an approach that is underutilized in D&I, can help with the development of actionable and brief instruments. This paper provides an overview of IRT for D...

Mattering, defined as feeling valued and adding value, is a basic psychological need with significant explanatory power. Although several specific measures have been introduced to assess the construct, no integrated, multidimensional measure exists. This limits the ability of researchers to investigate mattering in ecological contexts. This paper s...

Objective Food insecurity is a structural barrier to HIV care in peri-urban areas in South Africa (SA), where approximately 80% of households are moderately or severely food insecure. ⁽¹⁾ For people with HIV (PWH), food insecurity is associated with poor ART adherence and survival rates. Yet, measurement of food insecurity among PWH remains a chall...

This study presents a new approach to synthesizing differential item functioning (DIF) effect size: First, using correlation matrices from each study, we perform a multigroup confirmatory factor analysis (MGCFA) that examines measurement invariance of a test item between two subgroups (i.e., focal and reference groups). Then we synthesize, across t...

Rhythmic entrainment occurs when an auditory rhythm drives an internal movement oscillator, thus providing a continuous time reference that improves temporal and spatial movement parameters. Entrainment processes and outcomes are well known for adults, but research is lacking for infants who might benefit from diagnosis and treatment of irregular r...

Response time information has recently attracted a significant amount of attention in the literature as it may provide meaningful information about item preknowledge. The methods that propose the use of response time information in identifying examinees with potential item preknowledge make an implicit assumption that the examinees with item prekno...

Aim/Purpose: The purpose of this study was to examine the factor structure of a newly developed Culture of Mattering survey (CoM) that evaluates mattering in the context of relationships with supervisors, colleagues, and the organization as a whole. Background: Mattering can be defined as the experience of feeling valued and adding value. Despite t...

Unusual response similarity among test takers may occur in testing data and be an indicator of potential test fraud (e.g., examinees copy responses from other examinees, send text messages or pre-arranged signals among themselves for the correct response, item pre-knowledge). One index to measure the degree of similarity between two response vector...

Piecewise mixed-effects models are useful for analyzing longitudinal educational and psychological data sets to model segmented change over time. These models offer an attractive alternative to commonly used quadratic and higher-order polynomial models because the coefficients obtained from fitting the model have meaningful substantive interpretati...

The purpose of the present study was to evaluate various analytical means to detect academic cheating in an experimental setting. The omega index was compared and contrasted given a gold criterion of academic cheating which entailed a discrepant score between two administrations using an experimental study with real test takers. Participants were 1...

This study compared the acoustic parameters and degree of perceived warmth in two types of infant-directed (ID) songs − the lullaby and the playsong − between mothers of infants with Down syndrome (DS) and mothers of typically-developing (TD) infants. Participants included mothers of 15 DS infants and 15 TD infants between 3 and 9 months of age. Ea...

The dimensionality of a set of items is important for scale development. In practice, tools that make use of eigenvalues are often used to assess dimensionality. Parallel analysis is featured here as it is becoming an increasingly popular method for assessing the number of dimensions, and computational tools have recently been made available which...

This study compared the acoustic parameters and degree of perceived warmth in two types of infant-directed (ID) songs − the lullaby and the playsong − between mothers of infants with Down syndrome (DS) and mothers of typically-developing (TD) infants. Participants included mothers of 15 DS infants and 15 TD infants between 3 and 9 months of age. Ea...

Unusual response similarity among test takers may occur in testing data and be an indicator of potential test fraud (e.g., examinees copy responses from other examinees, send text messages or pre-arranged signals among themselves for the correct response, item pre-knowledge). One index to measure the degree of similarity between two response vector...

We describe a patient LS, profoundly deaf in both ears from birth, with underdeveloped superior temporal gyri. Without hearing aids, LS displays no ability to detect sounds below a fixed threshold of 60 dBs, which classifies him as clinically deaf. Under these no-hearing-aid conditions, when presented with a forced-choice paradigm in which he is as...

This article describes the REREFACT R package, which provides a postrotation algorithm that reorders or reflects factors for each replication of a simulation study with exploratory factor analysis (EFA). The purpose of REREFACT is to provide a general algorithm written in freely available software, R, dedicated to addressing the possibility that a...

Test fraud has recently received increased attention in the field of educational testing, and the use of comprehensive integrity analysis after test administration is recommended for investigating different types of potential test frauds. One type of test fraud involves answer copying between two examinees, and numerous statistical methods have bee...

Nonlinear random coefficient models (NRCMs) for continuous longitudinal data are often used for examining individual behaviors that display nonlinear patterns of development (or growth) over time in measured variables. As an extension of this model, this study considers the finite mixture of NRCMs that combine features of NRCMs with the idea of fin...

The performance of item selection methods in multidimensional computerized adaptive testing has only been studied using an independent cluster multidimensional structure. The goal of this study is to examine the effect of four different item selection methods on test utilization and measurement accuracy under more complex multidimensional data stru...

Among the methods proposed for identifying the number of latent traits in multidimensional IRT models, DETECT has attracted the attention of both methodologists and applied researchers as a nonparametric counterpart to other procedures. The current study investigated the overall performance of the DETECT procedure and its outcomes using a real-data...

A linear-linear piecewise growth mixture model (PGMM) is appropriate for analyzing segmented (disjointed) change in individual behavior over time, where the data come from a mixture of 2 or more latent classes, and the underlying growth trajectories in the different segments of the developmental process within each latent class are linear. A PGMM a...

A linear–linear piecewise growth mixture model (PGMM) is appropriate for analyzing segmented (disjointed) change in individual behavior over time, where the data come from a mixture of 2 or more latent classes, and the underlying growth trajectories in the different segments of the developmental process within each latent class are linear. A PGMM a...

Effective instructional planning and intervening rely heavily on accurate understanding of students' growth, but relatively few researchers have examined mathematics achievement trajectories, particularly for students with special needs. We applied linear, quadratic, and piecewise linear mixed-effects models to identify the best-fitting model for m...

The purpose of the present study was to explore the influence of the number of targets specified on the quality of exploratory factor analysis solutions with a complex underlying structure and incomplete substantive measurement theory. We extended previous research in this area by (a) exploring this phenomenon in situations in which both the common...

Background: The mission of state early intervention (EI) programs under IDEA is to provide services and supports to both children 0-3 with developmental delays and their families. Since 2005, states have been required to report on families’ perceptions of the extent to which EI helped the family achieve desired family outcomes. Families of a child...

This study examined the effect of baseline estimation on the quality of trend estimates derived from Curriculum Based Measurement of Oral Reading (CBM-R) progress monitoring data. The authors used a linear mixed effects regression (LMER) model to simulate progress monitoring data for schedules ranging from 6-20 weeks for datasets with high and low...

Curriculum-Based Measurement of Oral Reading (CBM-R) is used to collect time series data, estimate the rate of student achievement, and evaluate program effectiveness. A series of 5 studies were carried out to evaluate the validity, reliability, precision, and diagnostic accuracy of progress monitoring across a variety of progress monitoring durati...

The generalized binomial test (GBT) and ω indices are the most recent methods suggested in the literature to detect answer copying behavior on multiple-choice tests. The ω index is one of the most studied indices, but there has not yet been a systematic simulation study for the GBT index. In addition, the effect of the ability levels of the examine...

This study compares two algorithms, as implemented in two different computer softwares, that have appeared in the literature for estimating item parameters of Samejima's continuous response model (CRM) in a simulation environment. In addition to the simulation study, a real-data illustration is provided, and CRM is used as a potential psychometric...

The plausible range of intra-class correlation coefficient (ICC) is essential for both a priori sample size calculations in planning cluster-randomized trials and statistical adjustments of misaligned analysis of clustered data in meta-analytic studies. Recent efforts to create databases for ICC in educational achievement outcomes are based on the...

Curriculum-based measurement of oral reading (CBM-R) is used to index the level and rate of student growth across the academic year. The method is frequently used to set student goals and monitor student progress. This study examined the diagnostic accuracy and quality of growth estimates derived from pre-post measurement using CBM-R data. A linear...

Curriculum-based measurement of oral reading (CBM-R) is frequently used to set student goals and monitor student progress. This study examined the quality of growth estimates derived from CBM-R progress monitoring data. The authors used a linear mixed effects regression (LMER) model to simulate progress monitoring data for multiple levels of progre...