The aim of this paper was to describe, and when possible compare, the multivariate methods used by the participants in the EADGENE WP1.4 workshop.
The validation of the multivariate methods was realized by analyzing their synthetic mixtures.
The validation of the multivariate methods was realised by analysing the synthetic mixtures of hydrochlorothiazide and spironolactone.
Results: A repeated-measures analysis of variance by using the multivariate method yielded a 35% lower mean velocity (F1,13 = 5.83, P =.031), a 110% larger segment length variability (F1,13 = 9.72, P =.008) and a 60% larger variability of movement time per segment (F1,13 = 5.78, P =.032) in RSD patients.
The predictive capability of the multivariate method developed by partial least squares regression was satisfactory, allowing mean errors between 0.33 and 10% in the simultaneous determination of ATZ, DIA and DEA in aqueous solution.
The resulting [96 × 731] data matrix was processed by the following multivariate methods: Partial Least Squares Discriminant Analysis (PLS-DA) was carried out to compress the raw data to a smaller number of variables, and to look for evidence of grouping according to disease state ("Y" variable is the class membership).
That, is better exploiting the temporal information in the virtual sensor by using multivariate methods, one can improve the discrimination capability of the MEG measurement beyond source localization by identifying functionally diverse behaviours (distinct response modes of the underlying network) within the same source signal.
By the multivariate delta method, the asymptotic distribution of (boldsymbol {hat {theta }}) is also approximately normal with mean θ and covariance matrix D Σ D ′, where D is the (p+3)×(p+3) diagonal matrix (diag(boldsymbol {hat {alpha }},1,1,ldots,1)) and (boldsymbol {hat {alpha }}=exp {(boldsymbol {hat {alpha }}^).
The clustering is made by the use of multivariate methods.
A meta-analysis based on the individual data of the patients included in studies (Stewart and Parmar, 1993) would help to define by multivariate methods the prognostic role of Bcl-2, but it would require the collection of a huge amount of retrospective data, with the potential problem of dealing with a lot of missing data.
