Curriculum Vitae
Nathaniel E. Helwig
Contact Information
University: Department of Psychology & School of Statistics,University of Minnesota
Address: Psych: N650 Elliot Hall, 75 E River Road, Minneapolis, MN 55455, USA Stat: 375 Ford Hall, 224 Church Street SE, Minneapolis, MN 55455, USA
Email: [email protected] Alt. Email: [email protected]
Websites: http://www.psych.umn.edu/people/facultyprofile.php?UID=helwig http://stat.umn.edu/~helwig/
Higher Education
May2013 Doctor of Philosophy inQuantitative Psychology
Department of Psychology, University of Illinois, Champaign, IL, USA Thesis: Fast and stable smoothing spline analysis of variance models for large
samples with applications to electroencephalography data analysis
Dec 2011 Master of Arts inPsychology
Department of Psychology, University of Illinois, Champaign, IL, USA Thesis: Parallel factor analysis of gait waveform data: A multimode extension
of principal component analysis
Dec 2010 Master of Science in Statistics
Department of Statistics, University of Illinois, Champaign, IL, USA
Recent Academic Appointments
Aug2014 Position: Assistant Professor
toPresent Location: Department of Psychology and School of Statistics University of Minnesota: Twin Cities
Aug2013 Position: Visiting Assistant Professor toAug 2014 Location: Department of Statistics
Teaching Experience
Undergrad Introduction to Statistics, Department of Psychology,University of Illinois
Level Applied Statistics, Department of Statistics, University of Illinois Nonparametric Methods, School of Statistics, University of Minnesota
Graduate Statistical Methods I, Department of Psychology,University of Illinois
Level Statistical Methods II, Department of Psychology, University of Illinois Multivariate Analysis, Department of Psychology, University of Illinois Advanced Data Analysis, Department of Statistics, University of Illinois
Journal Publications
Helwig, N. E., & Ma, P. (in press). Fast and stable multiple smoothing parameter selec-tion in smoothing spline analysis of variance models with large samples. Journal of Computational and Graphical Statistics
doi:
Helwig, N. E., & Anderson, C. J. (2014). Review of Handbook of Advanced Multilevel Analysis by J. J. Hox & J. K. Roberts (Eds.). Psychometrika, 79, 175–177.
doi: 10.1007/S11336-013-9351-3
Helwig, N. E.(2013). The special sign indeterminacy of the direct-fitting Parafac2 model: Some implications, cautions, and recommendations for Simultaneous Component Anal-ysis. Psychometrika, 78, 725–739.
doi: 10.1007/S11336-013-9331-7
Helwig, N. E., & Hong, S. (2013). A critique of Tensor Probabilistic Independent Compo-nent Analysis: Implications and recommendations for multi-subject fMRI data analy-sis. Journal of Neuroscience Methods, 213, 263–273.
doi: 10.1016/j.jneumeth.2012.12.009
Helwig, N. E., Hong, S., & Bokhari, E. (2013). Analyzing individual and group differences in multijoint multiwaveform gait data using the Parafac2 model. International Journal for Numerical Methods in Biomedical Engineering, 29, 62–82.
doi: 10.1002/cnm.2492
Helwig, N. E., Hong, S., & Polk, J. D. (2012). Parallel Factor Analysis of gait waveform data: A multimode extension of Principal Component Analysis. Human Movement Science, 31, 630–648.
∗Helwig, N. E., Hong, S., Hsiao-Wecksler E. T., & Polk, J. D. (2011). Methods to
tempo-rally align gait cycle data. Journal of Biomechanics, 44, 561–566. doi: 10.1016/j.jbiomech.2010.09.015
Manuscripts Under Review or In Preparation
Helwig, N. E., & Ma, P. (in preparation). Stable smoothing spline approximation via bin-sampled knots.
Helwig, N. E., & Ma, P. (in preparation). Nonparametric Gaussian regression for ultra large samples: Scalable computation via rounding parameters.
Bokhari, E., Hong, S.,Helwig, N. E., Polk, J. D., & Ragetly, C. A. (in preparation). Exam-ining cranial cruciate ligament deficiency and its effect on canine gait using Parafac2.
Software Packages
Helwig, N. E. (2014). bigsplines: Smoothing splines for large samples.
R package version 1.0-3. http://CRAN.R-project.org/package=bigsplines
Invited Talks
Helwig, N. E. (2014, Aug. 8–10). Fast and stable smoothing spline analysis of variance models for large samples with applications to electroencephalography data analysis. Presented at the APA Convention, Washington D.C., United States.
Helwig, N. E. (2014, Aug. 2–7). Smoothing spline analysis of variance models for elec-troencephalography data analysis. Presented at the Joint Statistical Meetings, Boston, Massachusetts, United States.
Helwig, N. E. (2014, May 28–30). Semiparametric regression of big data in R. Presented at the Computational Science and Engineering Big Data/Data Analytics Research Conference, Champaign, Illinois, United States.
Helwig, N. E., & Ma, P. (2013, Aug. 3–8). Fast and stable multiple smoothing parameter selection in smoothing spline analysis of variance models with large samples. Presented at the Joint Statistical Meetings, Montreal, Quebec, Canada.
Helwig, N. E. (2013, Mar. 4). Smoothing spline analysis of variance models: Theory and model building. Presented at the Quantitative Psychology Brownbag Meeting, Champaign, Illinois, United States.
∗Article was selected as a “Pick of the Week” in March, 2011 by BIOMCH-L (the listserve sponsored by the International Society of Biomechanics).
Helwig, N. E., Hong, S., Polk, J. D., & Bokhari, E. (2011, Jan. 31). Analysis of multi-mode gait waveform data using the Parafac and Parafac2 multi-models. Presented at the Quantitative Psychology Brownbag Meeting, Champaign, Illinois, United States. Helwig, N. E., & Hong, S. (2009, June 14–19). Parallel factor analysis of gait data.
Presented at Three-way Methods in Chemistry and Psychology (TRICAP 2009), Vall de N´uria, Spain.
Helwig, N. E., & Hong, S. (2009, Apr. 20). Decomposing gait shapes using GPA and Parafac. Presented at the Quantitative Psychology Brownbag Meeting, Champaign, Illinois, United States.
Helwig, N. E., & Hong, S. (2008, Apr. 21). Multivariate analysis of human gait. Presented at the Quantitative Psychology Brownbag Meeting, Champaign, Illinois, United States.
Poster Presentations
Helwig, N. E. (2013, Apr. 24–25). A look into the mind of an alcoholic: Smoothing spline models for EEG data analysis. Presented at the Computational Science and Engineer-ing Annual MeetEngineer-ing (CSE 2013), Urbana, IL, USA.
Hsiao-Wecksler, E. T., Dankowicz, H., Hong, S., Lague, M. R., Polk, J. D., Rosengren K. S., Bokhari, E., DiBerardino, L. A. III, Helwig, N. E., & Park, K. (2011, Jan. 4–7). Quantitative characterization of complex motion patterns using shape-based and multivariate techniques. Presented at the National Science Foundation (NSF) Civil, Mechanical and Manufacturing Innovation (CMMI) Research and Innovation Confer-ence 2011, Atlanta, GA, USA.
Helwig, N. E., Hong, S., Polk, J. D., & Lague, M. R. (2010, Aug. 18–21). Analysis of gait cycle shapes using parallel factor analysis. Presented at the Annual Meeting for the American Society of Biomechanics (ASB 2010), Providence, RI, USA.
Helwig, N. E., Hong, S., & Hsiao-Wecksler, E. T. (2009, Aug. 26–29). Partitioning gait data into temporal and intensity differences. Presented at the Annual Meeting for the American Society of Biomechanics (ASB 2009), State College, PA, USA.
Helwig, N. E., Hong, S., & Hsiao-Wecksler, E. T. (2009, Aug. 26–29). Methods to time-normalize gait cycle data. Presented at the Annual Meeting for the American Society of Biomechanics (ASB 2009), State College, PA, USA.
Hsiao-Wecksler, E. T., Dankowicz, H., Hong, S., Lague, M. R., Polk, J. D., Rosengren K. S., DiBerardino, L. A. III, Helwig, N. E., & Park, K. (2009, June 22–25). Quanti-tative characterization of complex motion patterns using shape-based and multivariate techniques. Presented at the National Science Foundation (NSF) Civil, Mechanical
and Manufacturing Innovation (CMMI) Research and Innovation Conference 2009, Honolulu, HI, USA.
Technical Skills
Programming Languages: R, MATLAB, Fortran, C/C++, SQL Statistical Programs: R, MATLAB, SAS, SPSS, SYSTAT Other: LATEX, Mac OS, Unix/Linux, Windows
Academic and Professional Associations
Jan 2013 Member
toPresent Psychometric Society
Dec 2012 Member
toPresent Multiple Sections, American Statistical Association
Aug2010 Member
toPresent Division 5, American Psychological Association
Aug2010 Student Representative of the Membership Committee toAug 2011 Division 5, American Psychological Association
Aug2009 Graduate Student Organization Representative
toMay 2013 Quantitative Division, Department of Psychology, University of Illinois
Inducted Psi Chi Honor Society Member
May2006 University of Miami Chapter, University of Miami
Inducted Phi Beta Kappa Honor Society Member
Research Awards
Spring2014 Distinguished Dissertation Award
Division 5, American Psychological Association
Details: Received for my dissertation about nonparametric analysis of elec-troencephalography data, advised by Ping Ma.
Spring2013 Student Paper Competition Winner
Statistical Computing/Graphics Sections, American Statistical Association Details: Received for a paper entitled “Fast and stable multiple
smooth-ing parameter selection in smoothsmooth-ing spline analysis of variance models with large samples”, co-authored by Ping Ma.
Spring2013 Nancy Hirschberg Award
Department of Psychology, University of Illinois
Details: The Nancy Hirschberg Award is for excellent work done in one of Prof. Hirschberg’s areas of interest, i.e. individual difference, personality, human judgement, and multivariate analysis.
Spring2011 Woodrow Fellowship
Department of Psychology, University of Illinois
Details: The Woodrow Fellowship is awarded to the most promising grad-uate students in the Department of Psychology doing basic scien-tific research in the field of psychology.
Teaching Awards
Spring2010 Outstanding Quantitative Psychology Doctoral Student Department of Psychology, University of Illinois
Details: Our first award, in 2010, goes to Nate Helwig, for his extraordi-nary work as a teaching assistant in PSYC 406/407, the Depart-ment wide graduate statistics sequence. Nate has shown excel-lence and outstanding dedication to teaching.
Spring2010 Graduate Teaching Certificate
Center for Teaching Excellence, University of Illinois
Details: The Graduate Teacher Certificate is a program of the Center for Teaching Excellence (CTE) and is supported by campus academic units and the Graduate College. It is designed to encourage TAs to develop their teaching skills and reflective practice.
Spring2010 List of Teachers Ranked as Excellent by their Students &Fall 2009 Center for Teaching Excellence, University of Illinois
Details: The Instructor & Course Evaluation System (ICES) is used across campus as the official instructor and course evaluation for faculty and teaching assistants.