Alignment versus variation methods for clustering microarray time-series data

In the past few years, it has been shown that traditional clustering methods do not necessarily perform well on time-series data because of the temporal relationships involved in such data — this makes it a particularly difficult problem. In this paper, we compare two clustering methods that have been introduced recently, especially for gene expression time-series data, namely, multiple-alignment (MA) clustering and variation-based co-expression detection (VCD) clustering approaches. Both approaches are based on a transformation of the data that takes into account the temporal relationships, and have been shown to effectively detect groups of co-expressed genes. We investigate the performances of the MA and VCD approaches on two microarray time-series data sets and discuss their strengths and weaknesses. Our experiments show the superior accuracy of MA over VCD when finding groups of co-expressed genes.