„Infidelitãțile“ coeficientului de fidelitate Cronbach alfa

Cronbach alpha coefficient is still commonly used in research dedicated to the development of psychologicaltests. However, there is a certain lack of understanding of the significance of real and, especially, has its limits.The article presents the fundamental postulates of classical test theory and analyzes, in this context, the mainissues affecting the calculation and interpretation of Cronbach alpha coefficient: unidimensionality, internal consistency,item number, characteristics of the data, the sampling error. Finally, are summarized recommendationsof good practices on the use and reporting Cronbach's alpha.

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The Comparison Accuracy Estimation of Test Reliability Coefficients for National Chemistry Examination in Jambi Province on Academic Year 2014/2015

JKPK (Jurnal Kimia dan Pendidikan Kimia) ◽

10.20961/jkpk.v2i1.8740 ◽

2017 ◽

Vol 2 (1) ◽

pp. 34

Author(s):

Rida Sarwiningsih

Keyword(s):

Internal Consistency ◽

Classical Test Theory ◽

Reliability Coefficient ◽

Test Theory ◽

Test Reliability ◽

Estimation Accuracy ◽

Cronbach Alpha ◽

Classical Test ◽

Academic Year ◽

Reliability Coefficients

<p>This research aims to compare the internal consistency of reliability coefficient on classical test theory. Estimation accuracy of internal consistency reliability coefficient used several methods of the coefficient reliability formulation. The methods are Split-Half Method, Cronbach Alpha formula, and Kuder Richardson formula. Determination of the test reliability coefficients used also some formula and then their results were compared with the results of their estimation accuracy. This research is a quantitative descriptive. Data were analyzed based on responses of national chemistry examination in Jambi province on academic year 2014/2015. The data of students answer sheets were taken using proportional stratified random sampling technique. There are 200 students’ responses from 162 schools (132 public schools and 30 private schools) in Jambi province. The form of data were dichotomy data and analyzed using Split-Half Method. Their reliabilities were analyzed using Cronbach Alpha formula and Kuder Richardson formula. Reliability criteria used consist of five conditions, they are 0.5; 0.6; 0.7; 0.8 and 0.9. The results of this research indicated that (a) the coefficient of reliability in classical test theory developed by measurement experts (using Split-Half Method, Cronbach Alpha formula and Kuder Richardson formula) have varying estimates of accuracy; (b) average reliability coefficients have the precision estimation about of 0.78 up to 0.8; (c) the reliability coefficient using Spearman Brown formula was 0.78, with Rulon formula was 0.78, Flanagan formula was 0.77, Cronbach Alpha formula was 0.838, the KR20 formula was 0.838, and KR21 formula was 0.82<em>1.</em></p>

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Reliability

10.1093/med:psych/9780198527565.003.0015 ◽

2015 ◽

Author(s):

Susanne Hempel

Keyword(s):

Correlation Coefficient ◽

Internal Consistency ◽

Classical Test Theory ◽

Test Theory ◽

Coefficient Alpha ◽

Parallel Test ◽

Reliability Measure ◽

Classical Test

This chapter discusses reliability. It outlines the nature and purpose of reliability, classical test theory, measures of reliability (measure orientated reliability, parallel test, and test-retest) as well as internal consistency, inter-item correlation, coefficient alpha, and categorical judgements.

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Construct validity and internal consistency of the Brazilian version of Leisure Attitude Measurement for the elderly

Revista da Escola de Enfermagem da USP ◽

10.1590/s1980-220x2020000703710 ◽

2021 ◽

Vol 55 ◽

Author(s):

Vivian Carla de Castro ◽

Cremilde Aparecida Trindade Radovanovic ◽

Mara Solange Gomes Dellaroza ◽

Bruno Pedroso ◽

Eraldo Schunk Silva ◽

...

Keyword(s):

Construct Validity ◽

Internal Consistency ◽

Structural Model ◽

Leisure Activities ◽

The Elderly ◽

Attitude Measurement ◽

Alpha Coefficient ◽

Cronbach Alpha ◽

Cronbach Alpha Coefficient ◽

Brazilian Version

ABSTRACT Objective: To evaluate the construct validity and internal consistency of the Brazilian version of Leisure Attitude Measurement for the elderly. Method: Methodological study with a quantitative approach. The data were collected for three months through domiciliary visits to a random and representative sample of 384 elders. The internal consistency was measured through Cronbach alpha coefficient. Construct validity was evaluated through exploratory factor analysis. Factor extraction was conducted per principal components, following the Kaiser criterion, with rotation through Varimax solution. Results: The participants’ mean age was 70,9 and they were mostly women, married, living with relatives, with one to four years of education, and with an income of up to one minimum wage. The final model of the instrument has conserved three factors, under the parsimony criterion, explaining 50% of data variance, with a total of 27 items distributed across the cognitive, affective, and behavioral domains, with an overall Cronbach alpha coefficient of 0.89. Conclusion: The proposed structural model has shown construct validity and an appropriate internal consistency, explaining 50% of data variability. Its application can promote the understanding of social reality and encourage a positive attitude and elderly engagement in leisure activities.

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Translation and adaptation of the Vocal Fatigue Index into Spanish

Revista de Investigación e Innovación en Ciencias de la Salud ◽

10.46634/riics.29 ◽

2020 ◽

Vol 2 (2) ◽

pp. 4-13

Author(s):

Lady Catherine Cantor-Cutiva ◽

María Celina Malebrán Bezerra de Mello ◽

Eric J. Hunter

Keyword(s):

Internal Consistency ◽

Voice Disorders ◽

Fatigue Index ◽

English Version ◽

Alpha Coefficient ◽

Spanish Translation ◽

Vocal Fatigue ◽

Cronbach Alpha ◽

Cronbach Alpha Coefficient ◽

Vocal Fatigue Index

Aim: the purpose of this study was to translate and adapt the English version of the Vocal Fatigue Index (VFI) into the Spanish language. Methods: the English version of the Vocal Fatigue Index (VFI) was translated into Spanish by two bilingual speech-language pathologists, and then was back-translated into English. The Spanish VFI (o “Índice de Fatiga Vocal”, IFV) was administrated to a pilot group of 10 individuals, which revealed some small typographical and grammatical adjustments to the index. The final updated version was then administrated to 34 subjects (21 with voice disorders, and 13 without voice disorders). Internal consistency and scale reliability were analyzed using Cronbach alpha coefficient. Results: a high Cronbach alpha coefficient for the three factors (0.87) was obtained. The results of the item role in reliability of the Spanish VFI demonstrated that all of them showed a positive role according to this criterion. The results of the ANOVA indicate a statistically significant difference between groups on the three scores of the Spanish translation of the VFI. In comparison to the healthy participants, those with voice disorders obtained statistically significant higher scores for the Spanish VFI subscales. Conclusion: the present study suggests that the Spanish translation of the Vocal Fatigue Index has a good internal consistency and high reliability on each of the three factors. The results suggest that the Spanish VFI can be used reliably to identify persons with vocal fatigue and has good clinical validity.

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Escala de autoavaliação de competências digitais de professores. Procedimentos de construção e validação

Texto Livre Linguagem e Tecnologia ◽

10.17851/1983-3652.12.2.152-171 ◽

2019 ◽

Vol 12 (2) ◽

pp. 152-171

Author(s):

Sara Dias-Trindade ◽

José António Moreira ◽

Catarina S. Nunes

Keyword(s):

Construct Validity ◽

Internal Consistency ◽

Assessment Scale ◽

Alpha Coefficient ◽

Consistency Analysis ◽

Self Assessment ◽

Cronbach Alpha ◽

Cronbach Alpha Coefficient ◽

Self Evaluation ◽

Digital Fluency

RESUMO: Este trabalho apresenta um estudo que descreve os procedimentos de construção de uma escala de autoavaliação de competências digitais de professores e as suas qualidades psicométricas. Depois de algumas considerações sobre o construto e a sua operacionalização, efetuou-se a análise dos procedimentos da sua construção, realizou-se a análise de consistência interna através do cálculo do coeficiente alfa de Cronbach e a análise da validade do construto (análise fatorial exploratória e confirmatória). Para além de bons indicadores de validade, globalmente, as medidas aplicadas caracterizam-se por uma fidelidade boa e estruturas fatoriais interpretáveis. PALAVRAS-CHAVE: escala de autoavaliação; competências digitais docentes; fluência digital. ABSTRACT: This paper presents a study that describes the procedures for the construction of a self-assessment scale of teachers' digital competences and their psychometric qualities. After some considerations about the construct and its operationalization, the procedures of its construction were analysed, the internal consistency analysis was carried out through the calculation of the Cronbach alpha coefficient and the analysis of the construct validity (exploratory and confirmatory factorial analysis). In addition to good indicators of validity, overall, the applied measures are characterized by a good fidelity and interpretable factorial structures. KEYWORDS: self-evaluation scale; teachers' digital competences; digital fluency.

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Evaluating the Internal Consistency of Subtraction-Based and Residualized Difference Scores: Considerations for Studies of Event-Related Potentials

10.31234/osf.io/nqwz6 ◽

2020 ◽

Author(s):

Peter E Clayson ◽

Scott Baldwin ◽

Michael J. Larson

Keyword(s):

Individual Differences ◽

Internal Consistency ◽

Neural Activity ◽

Generalizability Theory ◽

Classical Test Theory ◽

Test Theory ◽

Difference Score ◽

Difference Scores ◽

Classical Test ◽

Score Reliability

In studies of event-related brain potentials (ERPs), difference scores between conditions in a task are frequently used to isolate neural activity for use as a dependent or independent variable. Adequate score reliability is a prerequisite for studies examining relationships between ERPs and external correlates, but there is a widely held view that difference scores are inherently unreliable and unsuitable for studies of individual differences. This view fails to consider the nuances of difference score reliability that are relevant to ERP research. In the present study, we provide formulas from classical test theory and generalizability theory for estimating the internal consistency of subtraction-based and residualized difference scores. These formulas are then applied to error-related negativity (ERN) and reward positivity (RewP) difference scores from the same sample of 117 participants. Analyses demonstrate that ERN difference scores can be reliable, which supports their use in studies of individual differences. However, RewP difference scores yielded poor reliability due to the high correlation between the constituent reward and non-reward ERPs. Findings emphasize that difference score reliability largely depends on the internal consistency of constituent scores and the correlation between those scores. Furthermore, generalizability theory estimates yielded higher internal consistency estimates for subtraction-based difference scores than classical test theory estimates did. Despite some beliefs that difference scores are inherently unreliable, ERP difference scores can show adequate reliability and be useful for isolating neural activity in studies of individual differences.

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