Eldad Davidov

An SEM Approach to Continuous Time Modeling of Panel Data: Relating Authoritarianism and Anomia

Panel studies, in which the same subjects are repeatedly observed at multiple time points, are among the most popular longitudinal designs in psychology. Meanwhile, there exists a wide range of different methods to analyze such data, with autoregressive and cross-lagged models being 2 of the most well known representatives. Unfortunately, in these models time is only considered implicitly, making it difficult to account for unequally spaced measurement occasions or to compare parameter estimates across studies that are based on different time intervals. Stochastic differential equations offer a solution to this problem by relating the discrete time model to its underlying model in continuous time. It is the goal of the present article to introduce this approach to a broader psychological audience. A step-by-step review of the relationship between discrete and continuous time modeling is provided, and we demonstrate how continuous time parameters can be obtained via structural equation modeling. An empirical example on the relationship between authoritarianism and anomia is used to illustrate the approach.

Testing the Stability of an Acquiescence Style Factor Behind Two Interrelated Substantive Variables in a Panel Design

This article addresses the question of to what extent one type of response style, called acquiescence (or agreeing response bias), is stable over time. A structural equation modeling approach is applied to measure the stability of one acquiescence factor behind two concepts among the same respondents for a 4-year period. The data used are representative population surveys in 1995 and 1999 from the Belgian Election Study in which balanced sets of items are used for measuring two interrelated constructs: perceived ethnic threat and distrust in politics. This study provides empirical support that acquiescence is stable and consistent for a 4-year period.

Testing for comparability of human values across countries and time with the third round of the European Social Survey

This study tests the compatibility and comparability of the human values measurements from the third round of the European Social Survey (ESS) to measure the 10 values from Schwartz’s (1992) value theory in 25 countries. Furthermore, it explains the dangers associated with ignoring non-invariance before comparing the values across nations or over time, and specifically describes how invariance may be tested. After initially determining how many values can be identified for each country separately, the comparability of value measurements across countries is assessed using multigroup confirmatory factor analysis (MGCFA). This is necessary to allow later comparisons of values’ correlates and means across countries. Finally, invariance of values over time (2002-07) is tested. Such invariance allows estimating aggregate value change and comparing it across countries meaningfully. In line with past results, only four to seven values can be identified in each country. Analyses reveal that the ESS value measurements are not suitable for measuring the 10 values; therefore, some adjacent values are unified. Furthermore, a subset of eight countries displays metric invariance for seven values, and metric invariance for six values is found for 21 countries. This finding indicates that values in these countries have similar meanings, and their correlates may be compared but not their means. Finally, temporal scalar invariance is evidenced within countries and over time thus allowing longitudinal value change to be studied in all the participating countries.

Using a Multilevel Structural Equation Modeling Approach to Explain Cross-Cultural Measurement Noninvariance

Testing for invariance of measurements across groups (such as countries or time points) is essential before meaningful comparisons may be conducted. However, when tested, invariance is often absent. As a result, comparisons across groups are potentially problematic and may be biased. In the current study, we propose utilizing a multilevel structural equation modeling (SEM) approach to provide a framework to explain item bias. We show how variation in a contextual variable may explain noninvariance. For the illustration of the method, we use data from the second round of the European Social Survey (ESS).

Explaining Attitudes Towards Immigration Policies in European Countries: The Role of Human Values

European societies have been experiencing increasing rates of immigration in recent decades. At the same time one can observe a substantial rise in anti-foreigner sentiments. In this study we investigate the effect of human values on attitudes towards immigration. We hypothesise that self-transcendent individuals are more supportive of, and conservative individuals are more adverse to, immigration. We do not expect large differences in the effect of values across contexts. To explain cross-country and cross-time differences we use group threat theory, according to which larger inflows of immigration combined with challenging economic conditions impose a threat on the host society, resulting in more negative attitudes towards immigration. To test our hypotheses we use data from the first three rounds of the European Social Survey (2002–03, 2004–05 and 2006–07) and multilevel analysis. Prior to the interpretation of the results, we guarantee that the concepts display measurement invariance across countries and over time. Our results largely confirm our hypotheses regarding the role that values play in the explanation of anti-immigration attitudes.

Diabetic retinopathy and health-related quality of life

ObjectiveTo describe the impact of co-morbidities, visual acuity, diabetic retinopathy (DR) grade, and macular edema (ME) on the health-related quality of life (HRQOL) among patients with diabetic retinopathy.MethodsAnalysis of data of 207 patients with diabetic retinopathy from Germany in 2003. HRQOL assessment was done using the generic (SF-12) questionnaire. It was hypothesized that exogenous variables (co-morbidities, visual acuity impairment, DR, and ME) would have an impact on HRQOL. Using a structural equation modelling procedure, the effects of exogenous variables on endogenous variables physical component summaries (PSC) and mental component summaries (MCS) reflecting HRQOL were tested.ResultsThe number of co-morbidities had a negative effect on visual acuity (b = −0.26, standardized) and a similar negative effect on PCS (b = −0.27). DR grade had a negative effect on visual acuity (b = −0.19) and a positive effect on the variable ME (b = 0.44). ME displayed a negative effect on visual acuity (b = −0.58) and also on MCS (b = −0.29). Visual acuity had a positive effect (b = 0.48) on PCS.ConclusionsPresence of DR and ME, visual acuity impairment and patient co-morbidities lead to significant impairment of both the physical and mental components of HRQOL.

Die Messung von Werten mit dem “Portraits Value Questionnaire”

Zusammenfassung: In zwei Stichproben wird eine deutschsprachige 40-Item Version des “Portraits Value Questionnaire” (PVQ) validiert; in einer dritten Stichprobe (European Social Survey) wird eine verkurzte Version mit 21 Items dieses Werteinventars validiert. Bei dem PVQ handelt es sich um ein von Shalom Schwartz neu entwickeltes Instrument zur Uberprufung seiner Theorie grundlegender menschlicher Werte. Die Aufgabenstellung des PVQ unterscheidet sich konzeptionell deutlich von der des bisher verwendeten Standardinstrumentes “Schwartz Value Survey” (SVS). Das neue Instrument ist besonders fur Probanden mit mittlerer und niedriger Schulbildung geeignet. Unsere Ergebnisse belegen die instrumentenunabhangige Validitat der von Schwartz postulierten Wertetheorie. Der Vergleich mit dem SVS belegt die konvergente und diskriminante Validitat der mit dem PVQ gemessenen zehn Wertetypen. Auch die vorhergesagten Beziehungen der Wertetypen mit zwei externen Konstrukten belegen die Konstruktvaliditat des PVQ. In einer ...

Three Approaches to Estimate Latent Interaction Effects: Intention and Perceived Behavioral Control in the Theory of Planned Behavior:

Interaction effects between explanatory constructs are an important part of many social theories. Analyses of interaction effects between variables using regression techniques have low power because they do not control for measurement errors. Therefore, latent interaction modeling using structural equation modeling (SEM) has been proposed as a better alternative to test for interaction effects. In contrast to traditional and complicated ‘constrained’ SEM approaches, two recent developments, the unconstrained approach and the residual centering approach, are especially attractive for applied researchers as they are much easier to implement. However, applied researchers still seem to be unsure about how to apply these approaches. In this study, we illustrate the use of the unconstrained and the residual centering approach and compare these approaches with the constrained approach of Algina and Moulder (2001) using data from a field study of 1,442 students. Theoretical background is the theory of planned behavior (Ajzen, 1991) in which we test the proposed interaction between an individuals intention to perform a behavior and perceived behavioral control (PBC) on behavior. The illustration should assist researchers interested in testing interaction effects using structural equation modeling.

The Cross-National Invariance Properties of a New Scale to Measure 19 Basic Human Values A Test Across Eight Countries

Several studies that measured basic human values across countries with the Portrait Values Questionnaire (PVQ-21) reported violations of measurement invariance. Such violations may hinder meaningful cross-cultural research on human values because value scores may not be comparable. Schwartz et al. proposed a refined value theory and a new instrument (PVQ-5X) to measure 19 more narrowly defined values. We tested the measurement invariance of this instrument across eight countries. Configural and metric invariance were established for all values across almost all countries. Scalar invariance was supported across nearly all countries for 10 values. The analyses revealed that the cross-country invariance properties of the values measured with the PVQ-5X are substantially better than those measured with the PVQ-21.Several studies that measured basic human values across countries with the Portrait Values Questionnaire (PVQ-21) reported violations of measurement invariance. Such violations may hinder meaningful cross-cultural research on human values because value scores may not be comparable. Schwartz et al. proposed a refined value theory and a new instrument (PVQ-5X) to measure 19 more narrowly defined values. We tested the measurement invariance of this instrument across eight countries. Configural and metric invariance were established for all values across almost all countries. Scalar invariance was supported across nearly all countries for 10 values. The analyses revealed that the cross-country invariance properties of the values measured with the PVQ-5X are substantially better than those measured with the PVQ-21.

Explaining habits in a new context: the case of travel-mode choice

It is often assumed that habits constitute an important component in human behavior. However, since the beginning of the century many sociologists have overlooked their role in explaining behavior. In this article we are testing empirically the completeness of an economic model made by Stigler and Becker to explain the effect of habit on behavior in a new context. According to the model habits are economically efficient in many cases. However, when an individual is faced with a permanent change in the environment, behavior is not determined by habits, but by the amount invested in information on the best options. We collected data from a field experiment on travel-mode choice with an intervention program to change the behavior of people moving to a new town. The intervention included information on available public transportation. Habit was measured by the subjects judgments of the likelihood that using public transport will take place in different kinds of situations. Theory was confirmed by the empirical data: there was no effect of habits on behavior in the new context. People in the intervention group used public transportation more often. However, search for information prior to the move had no effect. Some socio-economic variables had an additional effect on behavior in contrast to theory. People with a car at their disposal and those with higher education used the car more often.