SPACI score report for 4ps8 in ASTRAL 2.07:

WARNING! The SPACI score for this entry is not valid. The PROCHECK parameters for this entry could not be obtained, and poor results have been arbitrarily assumed.

PDB Entry: 4ps8
SPACI score: 0.18 (not valid)
AEROSPACI score: 0.18 (not valid)

Experiment type: XRAY
Resolution: 2.99
R-factor: 0.197
PCK1 PROCHECK Ramachandran: N/A
PCK2 PROCHECK Chi-1 angle: N/A
PCK3 PROCHECK H-bonds: N/A
WCK1 WHAT_CHECK Packing: -1.931
WCK2 WHAT_CHECK Ramachandran: -3.985
WCK3 WHAT_CHECK Chi angles: -4.429
WCK4 WHAT_CHECK Backbone: 2.81

Note: Here are links to pages about PROCHECK and WHAT_CHECK.

Here is the full WHAT_CHECK report on this protein (linked from the WHAT_CHECK site).