Search Results - "Oscar Olvera"

The relationship between statistical power and predictor distribution in multilevel logistic regression: a simulation-based approach by Olvera Astivia, Oscar L, Gadermann, Anne, Guhn, Martin

“…Despite its popularity, issues concerning the estimation of power in multilevel logistic regression models are prevalent because of the complexity involved in…”
Get full text

Simultaneous estimation of the intermediate correlation matrix for arbitrary marginal densities by Olvera Astivia, Oscar L., Kroc, Edward, Zumbo, Bruno D.

“…A popular approach to the simulation of multivariate, non-normal data in the social sciences is to define a multivariate normal distribution first, and then…”
Get full text

The case for the curve: Parametric regression with second- and third-order polynomial functions of predictors should be routine by Kroc, Edward, Olvera Astivia, Oscar L

“…Polynomial regression is an old and commonly discussed modeling technique, though recommendations for its usage are widely variable. Here, we make the case…”
Get full text

The Importance of Thinking Multivariately When Setting Subscale Cutoff Scores by Kroc, Edward, Olvera Astivia, Oscar L.

“…Setting cutoff scores is one of the most common practices when using scales to aid in classification purposes. This process is usually done univariately where…”
Get full text

Centering in Multiple Regression Does Not Always Reduce Multicollinearity: How to Tell When Your Estimates Will Not Benefit From Centering by Olvera Astivia, Oscar L., Kroc, Edward

“…Within the context of moderated multiple regression, mean centering is recommended both to simplify the interpretation of the coefficients and to reduce the…”
Get full text

Many nonnormalities, one simulation: Do different data generation algorithms affect study results? by Fairchild, Amanda J., Yin, Yunhang, Baraldi, Amanda N., Astivia, Oscar L. Olvera, Shi, Dexin

“…Monte Carlo simulation studies are among the primary scientific outputs contributed by methodologists, guiding application of various statistical tools in…”
Get full text

The Role of Item Distributions on Reliability Estimation: The Case of Cronbach’s Coefficient Alpha by Olvera Astivia, Oscar Lorenzo, Kroc, Edward, Zumbo, Bruno D.

“…Simulations concerning the distributional assumptions of coefficient alpha are contradictory. To provide a more principled theoretical framework, this article…”
Get full text

Electrochemical dissolution of chalcopyrite in the presence of thiourea and formamidine disulfide by Olvera, Oscar G., Rebolledo, Monserrat, Mora, Nelson, Dixon, David G., Asselin, Edouard

“…The effects of thiourea (TU) and formamidine disulfide (FDS) on the electrochemical dissolution of chalcopyrite in sulfuric acid solution and at ambient…”
Get full text

A Cautionary Note on the Use of the Vale and Maurelli Method to Generate Multivariate, Nonnormal Data for Simulation Purposes by Olvera Astivia, Oscar L., Zumbo, Bruno D.

“…To further understand the properties of data-generation algorithms for multivariate, nonnormal data, two Monte Carlo simulation studies comparing the Vale and…”
Get full text

Kinetic study of the dissolution of metallic nickel in sulphuric acid solutions in the presence of different oxidants by Bilczuk, Dario, Olvera, Oscar G., Asselin, Edouard

“…The dissolution of metallic nickel particles in sulphuric acid solutions has been studied in this work. The effect of temperature, sulphuric acid…”
Get full text

The National Standard of Psychological Health and Safety in the Workplace: A Psychometric and Descriptive Study of the Nursing Workforce in British Columbia Hospitals by Havaei, Farinaz, Park, Minjeong, Astivia, Oscar L. Olvera

“…Background In 2013, the Mental Health Commission of Canada created a National Standard that includes 13 workplace factors associated with employee mental…”
Get full text

Prostaglandin analogues signal detection by data mining in the FDA Adverse Event Reporting System database by Contreras-Salinas, Homero, Romero-López, María Soledad, Olvera-Montaño, Oscar, Rodríguez-Herrera, Lourdes Yolotzin

“…ObjectiveThis study aims to identify safety signals of ophthalmic prostaglandin analogues through data mining the Food and Drug Administration Adverse Event…”
Get full text

Validation of a preclinical dry eye model in New Zealand white rabbits during and following topical instillation of 1% ophthalmic atropine sulfate by Sánchez‐Ríos, Alejandra, Correa‐Gallegos, Elba Yadira, Medina‐Espinoza, José Manuel, Navarro‐Sanchez, Andrea Anaid, Olvera‐Montaño, Oscar, Baiza‐Durán, Leopoldo, Muñoz‐Villegas, Patricia

“…Background The objective of this study was to validate an animal model for dry eye during and after the administration of 1% ophthalmic atropine sulfate (OAS)…”
Get full text

Population models and simulation methods: The case of the Spearman rank correlation by Astivia, Oscar L. Olvera, Zumbo, Bruno D.

“…The purpose of this paper is to highlight the importance of a population model in guiding the design and interpretation of simulation studies used to…”
Get full text

The Ages and Stages Questionnaire: Latent factor structure and growth of latent mean scores over time by Olvera Astivia, Oscar L., Forer, Barry, Dueker, Gwenden L., Cowling, Candace, Guhn, Martin

“…Very little research exists that looks at the Ages and Stages Questionnaire simultaneously from a modern latent variable point of view and by looking at its…”
Get full text

A Note on the General Solution to Completing Partially Specified Correlation Matrices by Olvera Astivia, Oscar L.

“…Partially specified correlation matrices (not to be confused with matrices with missing data or EM-correlation matrices) can appear in research settings such…”
Get full text

On the solution multiplicity of the Fleishman method and its impact in simulation studies by Olvera Astivia, Oscar L., Zumbo, Bruno D.

“…The Fleishman third‐order polynomial algorithm is one of the most‐often used non‐normal data‐generating methods in Monte Carlo simulations. At the crux of the…”
Get full text

Efficacy and Safety of an Ophthalmic DMPC-Based Nanoemulsion in Patients with Dry Eye Disease: A Phase I/II Randomized Clinical Trial by Baiza-Durán, Leopoldo M., Muñoz-Villegas, Patricia, Sánchez-Ríos, Alejandra, Olvera-Montaño, Oscar

“…Purpose. The goals of this study were to evaluate the safety and efficacy of an ophthalmic 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC)-based…”
Get full text

Evaluation of the Relationship Between Diabetic Macular Edema and Renal Function in a Latino Population by Torres-Arellano, José M., Tornero-Jimenez, Andrea, Sánchez-Ríos, Alejandra, Olvera-Montaño, Oscar, Muñoz-Villegas, Patricia

“…Introduction Diabetic macular edema (DME) is one of the leading causes of vision impairment. The relationship between DME and estimated glomerular filtration…”
Get full text

Effect of activated carbon on the thiosulfate leaching of gold by Olvera, Oscar G., Domanski, Daniel F.R.

“…The catalyzed thiosulfate leach of gold from oxide ores has been evaluated. The addition of fine activated carbon resulted in increased dissolution rates and…”
Get full text