How to parameterize box location prediction when using parametric queries in ablations

[yaruzz]

Thanks for your impressive work!
In the paper, Table 5 provides a comparison between using non-parametric queries and not. When using non-parametric queries, the box location is obtained by adding the offset prediction to the coordinates of the sampled query points. However, when using parametric queries, the sampling operation is removed. Is my understanding correct? In this case, how do you parameterize the box location? Do you regress the absolute location directly?