Referential density and relative (referential) density account for much of what makes fictional texts 'thick' or 'easy' reads. All other factors being equal, high density will make for difficult reading in that the reader is required to reconstruct the fictional world in a short space, whereas low density is characteristic of a high degree of action.
Referential density and relative (referential) density play a major role in determining whether a fictional text is dense or easy to read. When all other factors are similar, texts with higher density require readers to rapidly reconstruct the fictional world, making them harder to read, whereas those with lower density often feature intense action.