Browsing USN Open Archive by Author "Ergon, Rolf"
Now showing items 1-20 of 31
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A didactically motivated PLS prediction algorithm
Ergon, Rolf; Esbensen, Kim H. (Journal article; Peer reviewed, 2001)The intention of this paper is to develop an easily understood PLS prediction algorithm, especially for the control community. The algorithm is based on an explicit latent variables model, and is otherwise a combination ... -
A BLUP derivation of the multivariate breeder’s equation, with an elucidation of errors in BLUP variance estimates, and a prediction method for inbred populations
Ergon, Rolf (Peer reviewed; Journal article, 2022)The multivariate breeder's equation, Lande (1979), was derived from the Price equation Price (1970,1972). Here, I present a derivation based on the BLUP (best linear unbiased predictions) equations in matrix form, first ... -
Comparison of simple projection methods (OPLS, PLSO, and TP) for separation of predicting and non-predicting information in PLSR and PCR, with focus on DA
Ergon, Rolf (Peer reviewed; Journal article, 2014)Orthogonal projections to latent structures (OPLS) and target projection (TP) are two alternative methods for separation of predicting and non-predicting parts of the predictor matrix in partial least squares regression ... -
Compression into two-component PLS factorizations
Ergon, Rolf (Journal article; Peer reviewed, 2003)Partial least squares regression (PLSR) often requires more than two components also in the case of a scalar response variable. As shown in papers on orthogonal signal correction (OSC), it is possible to reduce the number ... -
Constrained numerical optimization of PCR/PLSR predictors
Ergon, Rolf (Journal article; Peer reviewed, 2003)Assuming a fully known latent variables (LV) model, the optimal multivariate calibration predictor is found from Kalman filtering theory. From this follows the best possible column space for a loading weight matrix Wopt. ... -
Delayed density-dependent onset of spring reproduction in a fluctuating population of field voles
Ergon, Torbjørn; Ergon, Rolf; Begon, Mike; Telfer, Sandra; Lambin, Xavier (Journal article; Peer reviewed, 2011)Delayed density-dependent demographic processes are thought to be the basis for multi-annual cyclic fluctuations in small rodent populations, but evidence for delayed density dependence of a particular demographic trait ... -
Dynamic system calibration by system identification methods
Ergon, Rolf; Di Ruscio, David Luigi (Chapter; Peer reviewed, 1997)Primary output variables from industrial processes can be estimated from known input variables and secondary process measurements. As a basis for this, the dynamic predictor has to be identi ed from data collected during ... -
Dynamic system multivariate calibration
Ergon, Rolf (Journal article; Peer reviewed, 1998)In the first part of the paper, the optimal estimator for normally nonmeasured primary outputs from a linear, time invariant and stable dynamic system is developed. The optimal estimator is based on all available information ... -
Dynamic system multivariate calibration based on multirate sampling data
Ergon, Rolf; Halstensen, Maths (Journal article; Peer reviewed, 2001) -
Dynamic system multivariate calibration for optimal primary output estimation
Ergon, Rolf (Doctoral thesis; Peer reviewed, 1999)In industrial plants and other types of dynamic systems, it is a common situation that measurements of primary system outputs are not available on-line. The primary outputs may for example be quality properties, that can ... -
Dynamic system multivariate calibration with low-sampling-rate y data
Ergon, Rolf; Halstensen, Maths (Journal article; Peer reviewed, 2000)When the data in principal component regression (PCR) or partial least squares regression (PLSR) form time series, it may be possible to improve the prediction/estimation results by utilizing the correlation between ... -
Dynamical BLUP modeling of reaction norm evolution, accommodating changing environments, overlapping generations, and multivariate data
Ergon, Rolf (Peer reviewed; Journal article, 2023)For theoretical studies, reaction norm evolution in a changing environment can be modeled by means of the multivariate breeder's equation, with the reaction norm parameters treated as traits in their own right. This is, ... -
Estimation, system identification and chemometrics
Ergon, Rolf; Di Ruscio, David Luigi; Esbensen, Kim H.; Hagen, Svein Thore (Conference report, 2000)In our master degree program in process automation, traditional modeling and control courses are supplemented by courses in experimental design and chemometrics. A corresponding inter-disciplinary research program supports ... -
Finding Y-relevant part of X by use of PCR and PLSR model reduction methods
Ergon, Rolf (Journal article; Peer reviewed, 2007)The paper is considering the following question: using principal component regression (PCR) or partial least squares regression (PLSR), how much data can be removed from X while retaining the original ability to predict ... -
The important choice of reference environment in microevolutionary climate response predictions
Ergon, Rolf (Peer reviewed; Journal article, 2022)It is well documented that individuals of wild populations can adjust to climate change by means of phenotypic plasticity, but few reports on adaptation by means of genetically based microevolution caused by selection. ... -
Informative PLS score-loading plots for process understanding
Ergon, Rolf (Journal article; Peer reviewed, 2004)Principal component regression (PCR) based on principal component analysis (PCA) and partial least squares regression (PLSR) are well known projection methods for analysis of multivariate data. They result in scores and ... -
Informative score-loading-contribution plots for multi-response process monitoring
Ergon, Rolf (Journal article; Peer reviewed, 2009)The projection based multivariate data methods of principal component regression (PCR) and partial least squares regression (PLSR) are well established in the eld of process monitoring. Use of score and loading plots for ... -
Microevolutionary system identification and climate response predictions
Ergon, Rolf (Peer reviewed; Journal article, 2022)Microevolutionary system identification was introduced Ergon (2022), with the specific purpose to show that predictions of genetic adaptations to climate change require that environmental reference values are properly ... -
Microevolutionary system identification and climate response predictions by use of BLUP prediction error method
Ergon, Rolf (Peer reviewed; Journal article, 2023)Animals and other organisms in wild populations may adjust to climate change by means of plasticity and evolution, and it is an important task to find the contributions from each of these effects. Attempts to solve this ... -
Modified Smith-predictor multirate control utilizing secondary process measurements
Ergon, Rolf (Journal article; Peer reviewed, 2007)The Smith-predictor is a well-known control structure for industrial time delay systems, where the basic idea is to estimate the non-delayed process output by use of a process model, and to use this estimate in an inner ...