J. O. Ramsay

ORCID: 0000-0002-0768-6303
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About
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Research Areas
  • Advanced Statistical Methods and Models
  • Statistical Methods and Inference
  • Statistical and numerical algorithms
  • Psychometric Methodologies and Testing
  • Control Systems and Identification
  • Soil Geostatistics and Mapping
  • Advanced Statistical Modeling Techniques
  • Advanced Control Systems Optimization
  • Time Series Analysis and Forecasting
  • Neural Networks and Applications
  • Optimal Experimental Design Methods
  • Spectroscopy and Chemometric Analyses
  • Fault Detection and Control Systems
  • Advanced Statistical Process Monitoring
  • Sensory Analysis and Statistical Methods
  • Statistical Methods in Clinical Trials
  • Speech and Audio Processing
  • Statistical Methods and Bayesian Inference
  • Computational Drug Discovery Methods
  • Advanced Numerical Analysis Techniques
  • Morphological variations and asymmetry
  • Probabilistic and Robust Engineering Design
  • Simulation Techniques and Applications
  • Birth, Development, and Health
  • Matrix Theory and Algorithms

McGill University
2016-2025

Bradley University
2019

University of North Carolina at Chapel Hill
2015

Politecnico di Milano
2015

Florida State University
2015

European Food Safety Authority
2012

Emory University
2011

Natural Sciences and Engineering Research Council
2008-2010

Simon Fraser University
2010

Vienna University of Economics and Business
2009

10.2307/1165264 article EN Journal of Educational and Behavioral Statistics 1999-01-01

SUMMARY Multivariate data analysis permits the study of observations which are finite sets numbers, but modern collection situations can involve data, or processes giving rise to them, functions. Functional involves infinite dimensional and/or data. The paper shows how theory L-splines support generalizations linear modelling and principal components samples drawn from random Spline smoothing rests on a partition function space into two orthogonal subspaces, one contains obvious structural...

10.1111/j.2517-6161.1991.tb01844.x article EN Journal of the Royal Statistical Society Series B (Statistical Methodology) 1991-07-01

Piecewise polynomials or splines extend the advantages of to include greater flexibility, local effects parameter changes and possibility imposing useful constraints on estimated functions. Among these is monotonicity, which can be an important property in many curve estimation problems. This paper shows virtues monotone through a number statistical applications, including response variable transformation nonlinear regression, variables multiple principal components canonical correlation,...

10.1214/ss/1177012761 article EN Statistical Science 1988-11-01

Summary We propose a new method for estimating parameters in models that are defined by system of non-linear differential equations. Such equations represent changes outputs linking the behaviour derivatives process to itself. Current methods from noisy data computationally intensive and often poorly suited realization statistical objectives such as inference interval estimation. The paper describes uses measurements on subset variables estimate defining approach is based modification...

10.1111/j.1467-9868.2007.00610.x article EN Journal of the Royal Statistical Society Series B (Statistical Methodology) 2007-10-25

10.1002/(sici)1521-4036(199804)40:1<56::aid-bimj56>3.0.co;2- article EN Biometrical Journal 1998-04-01

Scale discriminability is the ability of a measure to discriminate among individuals ordered along some continuum, such as depressive severity. We used nonparametric item-response model examine scale in Beck Depression Inventory (BDI) and Center for Epidemiologic Studies (CES-D) both college depressed outpatient samples. In sample, CES-D was more discriminating than BDI, but standard cutoff score 16 overestimated likely prevalence depression (45%). The may be effective BDI detecting...

10.1037/1040-3590.7.2.131 article EN Psychological Assessment 1995-06-01

Summary Many situations call for a smooth strictly monotone function f of arbitrary flexibility. The family functions defined by the differential equation D 2 =w Df, where w is an unconstrained coefficient comprises twice differentiable functions. solution to this = C 0 + 1 −1{exp(D −1 w)}, and are constants partial integration operator. A basis expanding suggested that permits explicit in expression f. In fitting data, it also useful regularize penalizing integral since measure relative...

10.1111/1467-9868.00130 article EN Journal of the Royal Statistical Society Series B (Statistical Methodology) 1998-07-01

10.1007/bf02293704 article EN Psychometrika 1982-12-01

Summary Functional data analysis involves the extension of familiar statistical procedures such as principal components analysis, linear modelling, and canonical correlation to where raw observation xi is a function. An essential preliminary functional often registration or alignment salient curve features by suitable monotone transformations hi argument t, so that actual analyses are carried out on values xi{hi(t)}. This referred dynamic time warping in engineering literature. In effect,...

10.1111/1467-9868.00129 article EN Journal of the Royal Statistical Society Series B (Statistical Methodology) 1998-07-01

Summary We describe a model for the analysis of data distributed over irregularly shaped spatial domains with complex boundaries, strong concavities and interior holes. Adopting an approach that is typical functional analysis, we propose spline regression computationally efficient, allows spatially covariate information can impose various conditions boundaries domain. Accurate surface estimation achieved by use piecewise linear quadratic finite elements.

10.1111/rssb.12009 article EN Journal of the Royal Statistical Society Series B (Statistical Methodology) 2013-03-20

The abundance of functional observations in scientific endeavors has led to a significant development tools for data analysis (FDA). This kind comes with several challenges: infinite-dimensionality function spaces, observation noise, and so on. However, there is another interesting phenomena that creates problems FDA. often lateral displacements/deformations curves, phenomenon which different from the height or amplitude variability termed phase variation. presence artificially inflates...

10.1214/15-sts524 article EN other-oa Statistical Science 2015-11-01

Abstract The authors develop a functional linear model in which the values at time t of sample curves yi (t) are explained feed‐forward sense by covariate xi(s) observed times s ±.t. They give special attention to case ± [t — δ, t], where lag parameter δ is estimated from data. use finite element method estimate bivariate regression function β(s, t), defined on triangular domain t. apply their problem predicting acceleration lower lip during speech basis electromyographical recordings muscle...

10.2307/3316063 article EN Canadian Journal of Statistics 2003-06-01
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