Moreover, the MSA used to compute rs3DDPD contained many gaps as it accounted for all class A GPCRs and not only the ones in the set. Therefore, lengthy rs3DDPDs with a large number of zeroes likely introduced noise in the model compared to the more compact ps3DDPDs. While this aspect would be corrected in practice by feature selection techniques prior to modelling, those were not applied here to be able to explicitly benchmark the calculated descriptor. Finally, ps3DDPDs represent the overall differences between proteins in the set, which seems to be beneficial in agreement with the observation from Rackovsky and Scheraga that the description of an overall mobility of the protein correlates better with its structure than the description of individual residue mobility .