BACKGROUND As microbial ecologists take advantage of high-throughput sequencing technologies to describe microbial communities across ever-increasing numbers of samples, new analysis tools are required to relate the distribution of microbes among larger numbers of communities, and to use increasingly rich and standards-compliant metadata to understand the biological factors driving these relati...

Two robust approaches to principal component analysis and factor analysis are presented. The different methods are compared, and properties are discussed. As an application we use a large geochemical data set which was analyzed in detail by univariate (geo-)statistical methods. We explain the advantages of applying robust multivariate methods.

Exploratory data analysis heavily relies on methods to visualize data and models in a user friendly and interpretable manner. We show how models consisting of a collection of fuzzy points can be visualized in parallel coordinates. In contrast to existing techniques that display only lines representing centroids or shaded areas showing the general variance of cluster centers, the proposed techni...

Numerous multivariate visualization techniques and systems have been developed in the past three decades to visually analyze and explore multivariate data being produced daily in application areas ranging from stock markets to the earth and space spaces. However, traditional multivariate visualization techniques typically do not scale well to large multivariate data sets, with the latter becomi...

objecitve: there have been contradictory findings on the relationship between socioeconomic status (ses) and child development although a wide range of results indicates that ses is associated with child development outcomes. the present study intended to define the relationship between ses and child development in tehran kindergartens. methods: this cross-sectional survey studied 1036 children...

the relative impacts of different types of land use on the surface water quality are yet to be ascertained and quantified. in this paper, the influence of different types of land use on surface water quality is investigated. rain events samples from different land use in the central plateau, iran, were analyzed for major ions. statistical analyses were employed to examine the statistical relati...

when the number of training samples is limited, feature reduction plays an important role in classification of hyperspectral images. in this paper, we propose a supervised feature extraction method based on discriminant analysis (da) which uses the first principal component (pc1) to weight the scatter matrices. the proposed method, called da-pc1, copes with the small sample size problem and has...

t is the purpose of this paper to contribute to the discussion initiated bywachter about the parallelism between principal component (pc) and atypological grade of membership (gom) analysis. the author testedempirically the close relationship between both analysis in a lowdimensional framework comprising up to nine dichotomous variables and twotypologies. our contribution to the subject is also...