Alexander de Leon

Associate Professor

Department of Mathematics and Statistics

PhD - Statistics

University of Alberta

Contact information

Phone

Office: 403.220.6782

Web presence

Website

Location

Office : MS588

Research and teaching

Research areas

  • Assessment of diagnostic tests
  • Copula models
  • Estimating functions and estimating equations
  • Joint models
  • Methods for correlated data
  • Mixed effects models
  • Models for mixed discrete and continuous outcomes
  • Pseudo- and composite likelihood methods
  • Statistical problems in medicine

Publications

Book chapter

  • de Leon, Alexander and Carriere Chough, K. "Analysis of mixed data: An overview" In Analysis of Mixed Data: Methods & Applications Chapman & Hall/CRC Press, 2013. 1-11. Print.
  • Wu, Beilei, de Leon, Alexander and Withange, Niroshan. "Joint analysis of mixed discrete and continuous outcomes via copulas" In Analysis of Mixed Data: Methods & Applications Chapman & Hall/CRC Press, 2013. 139-156. Print.
  • de Leon, Alexander and Carriere Chough, K. "Mixed-outcome data" Encyclopedia of Biopharmaceutical Statistics (3rd ed) Informa Healthcare, 2010. 817-822. Print.

Book review

  • de Leon, Alexander. Review of “Latent Markov Models for Longitudinal Data,” by F. Bartolucci, A. Farcomeni & F. Pennoni Technometrics, 2014. 57.1, 139. Print.

Edited book

  • de Leon, Alexander and Carriere Chough, K (eds). Analysis of Mixed Data: Methods & Applications Chapman & Hall/CRC Press, 2013. 262 pp. Print.

Journal article

  • Perera, Y, Ren, Mingchen, Punzalan, JB, Rudnisky, CJ and de Leon, Alexander. "Binocular sensitivity and specificity of screening tests in cross-sectional diagnostic studies of paired organs". Statistics in Medicine, 36.11 (2017): 1754-1766. Print.
  • Lu, D, Weljie, A, de Leon, Alexander, McConnell, Y, Bathe, OF and Kopciuk, Karen. "Performance of variable selection methods using stability-based selection". BMC Research Notes 10.143 (2017). Print.
  • Jiryaie, F, Withanage, N, Wu, B and de Leon, Alexander. "Gaussian copula distributions for mixed data, with application in discrimination". Journal of Statistical Computation & Simulation 86.9 (2016): 1643-1659. Print.
  • Withanage, N, de Leon, Alexander and Rudnisky, CJ. "Joint estimation of multiple disease-specific sensitivities and specificities via crossed random effects models for correlated reader-based diagnostic data: Application of data cloning". Statistics in Medicine 34.29 (2015): 3916-3928. Print.
  • Wu, Beilei and de Leon, Alexander. "Gaussian copula mixed models for clustered mixed outcomes, with application in developmental toxicology". Journal of Agricultural, Biological and Environmental Statistics 19.1 (2014): 39-56. Print.
  • Inan, G, Ilk-Dag, O and de Leon, Alexander. "Letter to the Editor re: "Logistic regression with multiple random effects: A simulation study of estimation methods and statistical packages," by Y. Kim, Y.-K. Choi, & S. Emery". American Statistician 68.2 (2014): 129-130. Print.
  • Withanage, N, de Leon, Alexander and Rudnisky, CJ. "Joint estimation of disease-specific sensitivities and specificities in reader-based multi-disease diagnostic studies of paired organs". Journal of Applied Statistics 41.10 (2014): 2282-2297. Print.
  • de Leon, Alexander, Mahmoodian, H and Jamalizadeh, A. "Distributional results for L-statistics based on random vectors with multivariate elliptical distributions". Chilean Journal of Statistics 4.1 (2013): 69-85. Print.
  • de Leon, Alexander and Punzalan, J. "An elementary proof of independence of least squares estimators of regression coefficients and of variance in linear regression". Philippine Statistician 62.1 (2013): 77-81. Print.
  • Wu, B and de Leon, Alexander. "Letter to the Editor re: "Sample size determination in clinical trials with multiple co-primary endpoints including mixed continuous and binary variables," by T. Sozu, T. Sugimoto, & T. Hamasaki". Biometrical Journal 55.5 (2013): 807-812. Print.
  • de Leon, Alexander and Wu, Beilei. "Copula-based regression models for a bivariate mixed discrete and continuous outcome". Statistics in Medicine 30.2 (2011): 175-185. Print.
  • de Leon, Alexander, Soo, A and Williamson, T. "Classification with discrete and continuous variables via general mixed-data models". Journal of Applied Statistics 38.5 (2011): 1021-1032. Print.
  • de Leon, Alexander, Soo, A, Bonzo, D and Rudnisky, C. "Joint estimation of diagnostic accuracy measures for paired organs-Application in ophthalmology". Biometrical Journal 51.5 (2009): 837-850. Print.
  • de Leon, Alexander and Zhu, Y. "ANOVA extensions for mixed discrete and continuous data". Computational Statistics & Data Analysis 52.4 (2008): 2218-2227. Print.
  • de Leon, Alexander. "One-sample likelihood ratio tests for mixed data". Communications in Statistics. A. Theory and Methods 36.1 (2007): 129-141. Print.
  • de Leon, Alexander, Guo, M, Rudnisky, CJ and Singh, G. "A likelihood approach to estimating sensitivity and specificity for binocular diagnostic data: Application in ophthalmology". Statistics in Medicine 26.17 (2007): 3300-3314. Print.
  • de Leon, Alexander and Carriere, KC. "General mixed-data model: Extension of general location and grouped continuous models". Canadian Journal of Statistics 35.4 (2007): 533-548. Print.
  • Rudnisky, CJ, Tennant, M, de Leon, Alexander, Hinz, B and Greve, M. "Benefits of stereopsis when identifying clinically significant macular edema via teleophthalmology". Canadian Journal of Ophthalmology 41.6 (2006): 727-732. Print.
  • de Leon, Alexander and Carriere, KC. "A generalized Mahalanobis distance for mixed data". Journal of Multivariate Analysis 92.1 (2005): 174-185. Print.
  • de Leon, Alexander. "Pairwise likelihood approach to grouped continuous model and its extension". Statistics and Probability Letters 75.1 (2005): 49-57. Print.
  • Somani, R, Tennant, M, Rudnisky, CJ, Weis, E, Ting, A, Greve, M, Hinz, B and de Leon, Alexander. "Comparison of stereoscopic digital imaging to film in the identification of macular degeneration". Canadian Journal of Ophthalmology 40.3 (2005): 293-302. Print.
  • Baker, C, Rudnisky, CJ, Tennant, M, Sanghera, P, Hinz, B, de Leon, Alexander and Greve, M. "JPEG compression of stereoscopic digital images for diagnosis of diabetic retinopathy via tele-ophthalmology". Canadian Journal of Ophthalmology 39.7 (2004): 746-754. Print.
  • Rudnisky, CJ, Hinz, B, Tennant, M, de Leon, Alexander and Greve, M. "High-resolution stereoscopic digital fundus photography versus contact-lens biomicroscopy for the detection of clinically significant macular edema". Ophthalmology 109.2 (2002): 267-274. Print.
  • de Leon, Alexander and Carriere, KC. "On the one-sample location hypothesis for mixed bivariate data". Communications in Statistics. A. Theory and Methods 29.11 (2000): 2573-2581. Print.

Other

  • Torabi, M and de Leon, Alexander. Conditional dependence in mixed models for a non-Gaussian longitudinal outcome 2017.
  • Wu, B, Inan, G and de Leon, Alexander. Joint analysis of correlated mixed data via Gaussian copula models with jittered binary outcomes 2016.
  • Ruan, Ji, Zhang, J and de Leon, Alexander. Impact of misspecified dependence on clustering of RNA-seq gene expression profiles 2016.
  • Ghahramani, Melody, Dag, Osman and de Leon, Alexander. Analysis of autocorrelated count data: A combined estimating function approach 2016.
  • Withange, Niroshan, Roy, M, Geys, H, Van der Leede, BJ and de Leon, Alexander. Conditional dependence in joint analysis of correlated non-Gaussian continuous outcomes 2014.
  • Wu, B, Akdur, H, Bonzo, Daniel and de Leon, Alexander. Sample size calculation in clinical trials with mixed binary and continuous co-primary endpoints: Application of Gaussian copula models 2014.
  • Wu, B, Roy, M and de Leon, Alexander. Joint analysis of multiple longitudinal mixed outcomes via Gaussian copula mixed models 2013.
  • de Leon, Alexander, Wu, Beilei and Punzalan, JB. Comparison of regression lines based on individual and averaged data 2010.