**3. Selected examples from literature using multivariate data analysis in waste management**

In the following chapter four selected examples using multivariate data analysis in waste management are described in detail. To illustrate the application of principal component analysis (PCA) the study by Mikhailov et al. [62] is presented. He carried out multivariate data analysis for the ecological assessment of landfills. The second example illustrates the application of partial least squares regression (PLS-R). Michel et al. [42] applied PLS-R to predict conventional parameters by spectroscopic data. Ros et al. [27] applied a cluster analysis to data of polymerase chain reaction coupled with denaturing gradient gel electrophoresis (PCR-DGGE) to observe the long-term effects of compost amendment on soil microbial activity. A soft independent model of class analogy (SIMCA) was applied by Malley et al. [8]. They used SIMCA to classify different composts according to their spectroscopic characteristic.
