Piecewise multivariate modelling of sequential metabolic profiling data.
BACKGROUND
Modelling the time-related behaviour of biological systems is essential for understanding their dynamic responses to perturbations. In metabolic profiling studies, the sampling rate and number of sampling points are often restricted due to experimental and biological constraints.


RESULTS
A supervised multivariate modelling approach with the objective to model the time-related variation in the data for short and sparsely sampled time-series is described. A set of piecewise Orthogonal Projections to Latent Structures (OPLS) models are estimated, describing changes between successive time points. The individual OPLS models are linear, but the piecewise combination of several models accommodates modelling and prediction of changes which are non-linear with respect to the time course. We demonstrate the method on both simulated and metabolic profiling data, illustrating how time related changes are successfully modelled and predicted.


CONCLUSIONS
The proposed method is effective for modelling and prediction of short and multivariate time series data. A key advantage of the method is model transparency, allowing easy interpretation of time-related variation in the data. The method provides a competitive complement to commonly applied multivariate methods such as OPLS and Principal Component Analysis (PCA) for modelling and analysis of short time-series data.
Rantalainen
Mattias
M
Research Group for Chemometrics, Institute of Chemistry, Umeå University, Umeå, S-901 87, Sweden. mattias.rantalainen@imperial.ac.uk
Cloarec
Olivier
O
Ebbels
Timothy M D
TM
Lundstedt
Torbjörn
T
Nicholson
Jeremy K
JK
Holmes
Elaine
E
Trygg
Johan
J
D000818:Animals; D019295:Computational Biology / Q000379:methods*; D003198:Computer Simulation; D003627:Data Interpretation, Statistical; D007687:Kidney Tubules, Proximal / Q000187:drug effects / Q000503:physiopathology; D007700:Kinetics; D008627:Mercuric Chloride / Q000633:toxicity; D008660:Metabolism; D008954:Models, Biological; D015233:Models, Statistical; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D051381:Rats; D012016:Reference Values; D049490:Systems Biology / Q000379:methods / Q000706:statistics & numerical data; D013997:Time Factors
D008627:Mercuric Chloride