Table 3.

The details of RCL-tree index structure.

Description	Yelp	Amap
Dataset size (MB)	131	209
Total of spatial textual objects	192,609	483,991
The size of $\mathbb{I}$ (MB)	345	3726
The size of $\mathbb{I}.\mathbb{R}$ (MB)	41	130
The size of $\mathbb{I}.\mathbb{L}$ (MB)	304	3596
The number of tree nodes in $\mathbb{I}.\mathbb{R}$	291,678	732,342
The number of concept lattices in $\mathbb{I}.\mathbb{L}$	11,142	27,930
The percentage of R-tree nodes linked with concept lattices	3.8%	3.8%
Average number of concepts in concept lattice	75	261
Average number of objects in concept lattice	52	52