Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 12 de 12
Filter
Add more filters











Publication year range
1.
Transp Res Part A Policy Pract ; 162: 80-103, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35665303

ABSTRACT

COVID-19 has been associated with a decline in public transport ridership in many cities. However, the impact of the pandemic on passenger perceptions of public transport, particularly loyalty, has remained largely unexplored. Using a case study of Tehran's bus system, this paper aims to assess the moderating effect of COVID-19 on passenger loyalty. A cross-sectional survey of bus users was conducted in two similar periods, before and during COVID-19. The data was analysed using structural equation modelling, with the effect of observed heterogeneity evaluated using multiple indicators multiple causes models and multi-group analysis. The results indicate that during COVID-19, perceptions of service quality have improved, particularly in relation to comfort (including crowding), safety, reliability and information. While this has led to increased customer satisfaction, loyalty to the system has decreased. An increase in the perceived attractiveness of using private cars was found to be the primary factor for reducing passenger loyalty with the perceived monetary and psychological costs of using cars being less effective in encouraging people to use the bus. Taking into account the significant utility of private vehicles in urban transportation during COVID-19, the present study identifies feasible areas for improving the performance of bus services to increase satisfaction with this form of public transport among car owners.

2.
Educ Psychol Meas ; 82(2): 254-280, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35185159

ABSTRACT

This article studies the Type I error, false positive rates, and power of four versions of the Lagrange multiplier test to detect measurement noninvariance in item response theory (IRT) models for binary data under model misspecification. The tests considered are the Lagrange multiplier test computed with the Hessian and cross-product approach, the generalized Lagrange multiplier test and the generalized jackknife score test. The two model misspecifications are those of local dependence among items and nonnormal distribution of the latent variable. The power of the tests is computed in two ways, empirically through Monte Carlo simulation methods and asymptotically, using the asymptotic distribution of each test under the alternative hypothesis. The performance of these tests is evaluated by means of a simulation study. The results highlight that, under mild model misspecification, all tests have good performance while, under strong model misspecification, the tests performance deteriorates, especially for false positive rates under local dependence and power for small sample size under misspecification of the latent variable distribution. In general, the Lagrange multiplier test computed with the Hessian approach and the generalized Lagrange multiplier test have better performance in terms of false positive rates while the Lagrange multiplier test computed with the cross-product approach has the highest power for small sample sizes. The asymptotic power turns out to be a good alternative to the classic empirical power because it is less time consuming. The Lagrange tests studied here have been also applied to a real data set.

3.
Article in English | MEDLINE | ID: mdl-36612950

ABSTRACT

The aim of this study is to analyze the factorial structure of the Multidimensional Body-Self Relations Questionnaire-Appearance Scales (MBSRQ-AS) to determine the adjustment of the study structure proposed in the Spanish short version in a young, non-clinical Chilean population and to evaluate the possible influence of sex, age, and BMI on body image measurement. The sample consisted of 614 Chilean youth (259 male and 355 female) between 15 and 28 years old (M = 18.81; SE = 2.46), from the Metropolitan Region, and four regions of the coast and south-central zone of the country. The average Body Mass Index (BMI) was 22.5 kg/m2 (SD = 3.16). The model fit was evaluated by confirmatory factor analysis (WLSMV) using the following: a model with a single general factor, a model with the five factors of the original version, a five-factor ESEM model, and a MIMIC model analyzed including sex, age, and BMI. The results show that the MIMIC sex, age, and BMI model presents an acceptable fit, observing that four factors, Appearance Orientation (AO), Body Areas Satisfaction (BAS), Overweight Preoccupation (OP), and Self-Classification Weight (SCW), are affected significantly for the sex variable, one for age, Appearance Evaluation (AE), and four for BMI (AE, BAS, OP, and SCW). In conclusion, MBSRQ-AS replicates the five-dimensional structure in a non-clinical sample of young Chileans; however, their scores are not invariant as they depend on sex, age, and BMI.


Subject(s)
Body Image , Humans , Male , Female , Adolescent , Young Adult , Adult , Psychometrics , Chile , Reproducibility of Results , Surveys and Questionnaires
4.
Appl Psychol Meas ; 44(2): 118-136, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32076356

ABSTRACT

In this article, the authors describe how multiple indicators multiple cause (MIMIC) models for studying uniform and nonuniform differential item functioning (DIF) can be conceptualized as mediation and moderated mediation models. Conceptualizing DIF within the context of a moderated mediation model helps to understand DIF as the effect of some variable on measurements that is not accounted for by the latent variable of interest. In addition, useful concepts and ideas from the mediation and moderation literature can be applied to DIF analysis: (a) improving the understanding of uniform and nonuniform DIF as direct effects and interactions, (b) understanding the implication of indirect effects in DIF analysis, (c) clarifying the interpretation of the "uniform DIF parameter" in the presence of nonuniform DIF, and (d) probing interactions and using the concept of "conditional effects" to better understand the patterns of DIF across the range of the latent variable.

5.
Liberabit ; 25(2): 139-158, jul.-dic. 2019. ilus, tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1143221

ABSTRACT

Objetivo: evaluar la estructura interna, invarianza de medida, validez de criterio y confiabilidad del CASM-85 en estudiantes de secundaria peruanos. Materiales y Métodos: se evaluaron 2075 estudiantes de ambos sexos, entre 11 y 18 años, provenientes de colegios nacionales y particulares de Arequipa, Chimbote, Lima y Pucallpa. Se realizó un análisis de la correlación ítem-ítem e ítemresto para cada dimensión del CASM-85, un análisis factorial confirmatorio y modelos MIMIC (Multiple Indicator, Multiple Cause) para evaluar la invarianza de medida a través de grupos según sexo, edad, colegio y ciudad. La confiabilidad fue estimada mediante los coeficientes Alpha y Omega. La validez de criterio entre el CASM-85 y el rendimiento académico se revisó a través de la r de Pearson y modelos de regresión. Resultados: se eliminaron ítems heterogéneos y se obtuvo una forma reducida de 45 ítems a compararse con su original de 53 ítems. Para la forma original el CFI y TLI fue < .9 en todas las ciudades, mientras que para la forma reducida fue < . 9 solo en Chimbote. Los SRMR y RMSEA fueron ≤ .10 y ≤ .09 para las formas original y reducida respectivamente. Los modelos MIMIC confirmaron invarianza para todas las variables excepto para la variable ciudad con la forma original (│ΔCFI│ = .09, │ΔTLI│ = .08). La confiabilidad fue moderada tanto para la forma original (Ω ≥ .68; α ≥ .81) como para la reducida (Ω ≥ .77; α ≥ .84). La r de Pearson mostró una relación positiva y de fuerza débil para la forma original (r = .17) y reducida (r = .18). Conclusión: la forma reducida del CASM-85 (45 ítems) ha mostrado mejores propiedades psicométricas que su forma original.


Objective: To assess the internal structure, measurement invariance, criterion validity and reliability of the CASM-85 in Peruvian high school students. Materials and methods: Two thousand seventy-five (2075) students of both sexes, aged 11 to 18 years, from public and private high schools of Arequipa, Chimbote, Lima and Pucallpa were evaluated. An item-item and item-rest correlation analysis for each dimension of the CASM- 85, a confirmatory factorial analysis and MIMIC (Multiple Indicator, Multiple Cause) models were used to evaluate the measurement invariance across the groups according to their sex, age, school and city. Reliability was estimated using alpha and omega coefficients. The criterion validity between the CASM-85 and academic performance was determined using Pearson’s r and regression models. Results: The heterogeneous items were removed, obtaining a 45-item short form compared to the original 53-item form. In the original form, CFI and TLI were < .9 in all the cities, whereas in the short form, CFI and TLI were < .9 only in Chimbote. SRMR and RMSEA were ≤ .10 and ≤ .09 in the original and short forms, respectively. The MIMIC models confirmed the measurement invariance in all variables, with the exception of the original form between cities (│ΔCFI│ = .09, │ΔTLI│= .08). Reliability was moderate for both the original (Ω ≥ .68; α ≥ .81) and short forms (Ω ≥ .77; α ≥ .84). Pearson’s r showed a positive and weak correlation in the original (r = .17, p < .001) and short (r = .18, p < .001) forms. Conclusion: The CASM-85 short form (45 items) has shown better psychometric properties than its original full form.

6.
Prev Vet Med ; 170: 104718, 2019 Oct 01.
Article in English | MEDLINE | ID: mdl-31421489

ABSTRACT

Brazil, one of the leading countries in livestock production, has not yet developed legislation considering animal welfare issues and most of the actions to improve farm animal welfare (FAW) standards are developed by livestock industries and government focusing in meet the demands of exporting countries. Such actions resulted in FAW protocols and manuals for adoption of best management practices. In this context, farmers' decisions are of particular importance as they may comply with current FAW protocols or even decide to provide better FAW standards than required. A present example of farmers' decisions to provide better FAW standards than required by FAW protocols is in the adoption of environmental enrichment in pig farming. This practice is widely available to pig farmers, however, anecdotal evidence shows that the adoption rate is low. This study uses the theory of planned behavior (TPB) as a framework to identify the socio-psychological factors that influence pig farmers' intention to adopt environmental enrichment on their farms. The TPB hypothesizes that intention is determined by three psychological constructs: attitude, subjective norms, and perceived behavioral control. These three constructs are derived from behavioral, normative, and control beliefs, respectively. Self-identity was added as an additional construct to explain intention. A survey with 185 farmers was conducted. We used Partial-Least-Square Structural Equation Modeling (PLS-SEM) to identify the impact of attitude, subjective norms, perceived behavioral control, and self-identity on farmers' intention to adopt environmental enrichment on their farms. We used MIMIC models to identify the most important beliefs underlying farmers' intention to adopt environmental enrichment in their farms. Results show that the intention of farmers to adopt was mainly determined by their positive perceptions about their own capability to adopt environmental enrichment (perceived behavioral control), followed by their perceptions about the social pressure to adopt it (subjective norms), their positive evaluations of adoption (attitude), and self-identity. The most important behavioral beliefs were 'increase productivity', and 'decrease animals stress'. The most important normative beliefs were 'family', 'neighbor farmers', 'pig buyers', and 'experts'. The most important control belief was 'receive bonus when selling pigs'. These results revealed important implications to design public and private interventions aimed to stimulate the adoption of animal friendly practices.


Subject(s)
Animal Welfare/statistics & numerical data , Attitude , Behavior Control , Farmers/psychology , Intention , Social Norms , Adult , Brazil , Female , Humans , Male , Middle Aged , Models, Psychological
7.
J Sport Exerc Psychol ; 41(1): 24-35, 2019 Feb 01.
Article in English | MEDLINE | ID: mdl-30909847

ABSTRACT

This study aimed to examine the factor structure, the simplex structure, and the self-determination continuum of the Youth Behavioral Regulation in Sport Questionnaire (YBRSQ); to test longitudinal invariance of the YBRSQ and to examine differential item functioning in the YBRSQ responses as a function of sex, type of sport, and competitive level; and to explore the dynamics of change and stability of motivational regulation across the competitive season in a sample of 736 adolescent athletes involved in intensive training settings across 3 measurement points (beginning, middle, and end). Results provided evidence of a simplex structure of YBRSQ scores and revealed differences between self-determination-theory-based measures of motivation in various contexts. Results revealed partial strict temporal invariance of the YBRSQ and did not reveal differential item functioning. Finally, the results demonstrated an increase in amotivation and external regulation and a decrease in intrinsic motivation across the season, probably because of daily pressures.


Subject(s)
Athletes/psychology , Motivation , Youth Sports/psychology , Adolescent , Female , Humans , Male , Models, Statistical , Personal Autonomy , Surveys and Questionnaires
8.
Biometrics ; 74(1): 127-134, 2018 03.
Article in English | MEDLINE | ID: mdl-28482110

ABSTRACT

Objective measures of oxygen consumption and carbon dioxide production by mammals are used to predict their energy expenditure. Since energy expenditure is not directly observable, it can be viewed as a latent construct with multiple physical indirect measures such as respiratory quotient, volumetric oxygen consumption, and volumetric carbon dioxide production. Metabolic rate is defined as the rate at which metabolism occurs in the body. Metabolic rate is also not directly observable. However, heat is produced as a result of metabolic processes within the body. Therefore, metabolic rate can be approximated by heat production plus some errors. While energy expenditure and metabolic rates are correlated, they are not equivalent. Energy expenditure results from physical function, while metabolism can occur within the body without the occurrence of physical activities. In this manuscript, we present a novel approach for studying the relationship between metabolic rate and indicators of energy expenditure. We do so by extending our previous work on MIMIC ME models to allow responses that are sparsely observed functional data, defining the sparse functional multiple indicators, multiple cause measurement error (FMIMIC ME) models. The mean curves in our proposed methodology are modeled using basis splines. A novel approach for estimating the variance of the classical measurement error based on functional principal components is presented. The model parameters are estimated using the EM algorithm and a discussion of the model's identifiability is provided. We show that the defined model is not a trivial extension of longitudinal or functional data methods, due to the presence of the latent construct. Results from its application to data collected on Zucker diabetic fatty rats are provided. Simulation results investigating the properties of our approach are also presented.


Subject(s)
Basal Metabolism , Energy Metabolism , Latent Class Analysis , Models, Statistical , Scientific Experimental Error , Animals , Humans , Observation , Oxygen Consumption , Rats , Rats, Zucker , Thermogenesis
9.
J Abnorm Child Psychol ; 44(8): 1559-1571, 2016 11.
Article in English | MEDLINE | ID: mdl-26783112

ABSTRACT

Co-occurring psychological disorders are highly prevalent among children and adolescents. To date, the most widely utilised factor model used to explain this co-occurrence is the two factor model of internalising and externalising (Achenbach 1966). Several competing models of general psychopathology have since been reported as alternatives, including a recent three factor model of Distress, Fear and Externalising Dimensions (Krueger 1999). Evidence for the three factor model suggests there are advantages to utilising a more complex model. Using the British Child and Adolescent Mental Health Survey 2004 data (B-CAMHS; N = 7997), confirmatory factor analysis was used to test competing factor structure models of child and adolescent psychopathology. The B-CAMHS was an epidemiological survey of children between the ages of 5 and 16 in Great Britain. Child psychological disorders were assessed using the Strength and Difficulties Questionnaire (Goodman 1997), and the Development and Wellbeing Assessment (Goodman et al. 2000). A range of covariates and risk variables including trauma, parent mental health and family functioning where subsequently utilised within a MIMIC model framework to predict each dimension of the 2 and three factor structure models. Two models demonstrated acceptable fit. The first complimented Achenbach's Internalising and Externalising structure. The three factor model was found to have highly comparable fit indices to the two factor model. The second order models did not accurately represent the data nor did an alternative three factor model of Internalising, Externalising and ADHD. The two factor and three factor MIMIC models observed unique profiles of risk for each dimension. The findings suggest that child and adolescent psychopathology may also be accurately conceptualised in terms of distress, fear and externalising dimensions. The MIMIC models demonstrated that the Distress and Fear dimensions have their own unique etiological profile of risk. This study directly informs future measurement models of child and adolescent psychopathology and demonstrates the effectiveness of a three factor model.


Subject(s)
Mental Disorders/etiology , Adolescent , Child , Factor Analysis, Statistical , Female , Health Surveys , Humans , Male , Mental Disorders/diagnosis , Mental Disorders/psychology , Mental Health , Models, Psychological , Psychopathology , Risk Factors , Surveys and Questionnaires
10.
Soc Sci Med ; 151: 56-68, 2016 Feb.
Article in English | MEDLINE | ID: mdl-26773293

ABSTRACT

How can one assess the quality of life of older people--particularly those with Alzheimer's disease--from the point of view of their opportunities to do valued things in life? This paper is an attempt to answer this question using as a theoretical framework the capability approach. We use data collected on 8841 individuals above 60 living in France (the 2008 Disability and Health Household Survey) and propose a latent variable modelling framework to analyse their capabilities in two fundamental dimensions: freedom to perform self-care activities and freedom to participate in the life of the household. Our results show that living as a couple, having children, being mobile and having access to local shops, health facilities and public services enhance both capabilities. Age, household size and male gender (for one of the two capabilities) act as impediments while the number of impairments reduces both capabilities. We find that people with Alzheimer's disease have a lower level and a smaller range of capabilities (freedom) when compared to those without, even when the latter have several impairments. Hence they need a special attention in policy-making.


Subject(s)
Health Status , Public Policy/trends , Alzheimer Disease , Female , France , Health Surveys , Humans , Male , Quality of Life/legislation & jurisprudence
11.
J Genet Psychol ; 176(3-4): 211-34, 2015.
Article in English | MEDLINE | ID: mdl-26135387

ABSTRACT

The gender similarities hypothesis by J. S. Hyde ( 2005 ), based on large-scale reviews of studies, concludes that boys and girls are more alike than different on most psychological variables, including academic skills such as reading and math (J. S. Hyde, 2005 ). Writing is an academic skill that may be an exception. The authors investigated gender differences in academic achievement using a large, nationally stratified sample of children and adolescents ranging from ages 7-19 years (N = 2,027). Achievement data were from the conormed sample for the Kaufman intelligence and achievement tests. Multiple-indicator, multiple-cause, and multigroup mean and covariance structure models were used to test for mean differences. Girls had higher latent reading ability and higher scores on a test of math computation, but the effect sizes were consistent with the gender similarities hypothesis. Conversely, girls scored higher on spelling and written expression, with effect sizes inconsistent with the gender similarities hypothesis. The findings remained the same after controlling for cognitive ability. Girls outperform boys on tasks of writing.


Subject(s)
Achievement , Intelligence/physiology , Mathematics , Reading , Writing , Adolescent , Adult , Child , Educational Measurement , Female , Humans , Male , Sex Factors , Young Adult
12.
Stat Med ; 33(25): 4469-81, 2014 Nov 10.
Article in English | MEDLINE | ID: mdl-24962535

ABSTRACT

Multiple indicators, multiple causes (MIMIC) models are often employed by researchers studying the effects of an unobservable latent variable on a set of outcomes, when causes of the latent variable are observed. There are times, however, when the causes of the latent variable are not observed because measurements of the causal variable are contaminated by measurement error. The objectives of this paper are as follows: (i) to develop a novel model by extending the classical linear MIMIC model to allow both Berkson and classical measurement errors, defining the MIMIC measurement error (MIMIC ME) model; (ii) to develop likelihood-based estimation methods for the MIMIC ME model; and (iii) to apply the newly defined MIMIC ME model to atomic bomb survivor data to study the impact of dyslipidemia and radiation dose on the physical manifestations of dyslipidemia. As a by-product of our work, we also obtain a data-driven estimate of the variance of the classical measurement error associated with an estimate of the amount of radiation dose received by atomic bomb survivors at the time of their exposure.


Subject(s)
Dyslipidemias/blood , Likelihood Functions , Nuclear Weapons , Radiation Dosage , Survivors , Female , Humans , Male
SELECTION OF CITATIONS
SEARCH DETAIL