Evaluate the collective function of references cited together in a given text segment.
Classify their combined role into one of the following categories: 'method', 'background', or 'result'.

Text:Further, we assume based on available experimental results (Pimanda et al., 2007b; Smith et al., 2008) that the increase in the transcriptional rate occurs via modulation of the state of chromatin rather than through direct interaction with transcriptional machinery.
Category: