A common underlying representation reflecting the similarity between the objects was the starting point to compare the locations of category centers for the different language groups in the current study. Unlike the research of Ameel et al. (2009), the sorting task was only performed by monolingual Dutch speaking participants. For every participant an individual similarity matrix was calculated based on how the stimuli were grouped together. If two stimuli were sorted into the same pile this was indicated with 1 in the similarity matrix, if two stimuli were sorted in separate piles this was indicated with 0. Since participants were allowed to cluster piles, some additional calculations were done depending on the number of piles within one cluster. For example, if a participant clustered two piles, the stimulus pairs within one pile still received 1, but stimulus pairs within the same cluster, but not sharing the same pile, received 0.5. In the case three piles were clustered again, stimulus pairs in the same pile received 1, stimulus pairs within the cluster but not sharing the same pile received 0.33. Therefore, the number of piles within a cluster was taken into account as well. The reliability of the sorting data was estimated using the split-half technique followed by the Spearman-Brown formula. The average pairwise similarity for 10,000 random splits of the sorting data reached 0.92 and thus proves to be highly reliable.