SPACI score report for 1by3 in ASTRAL 1.55:

PDB Entry: 1by3
SPACI score: 0.3
AEROSPACI score: 0.3

Experiment type: XRAY
Resolution: 2.74
R-factor: 0.186
PCK1 PROCHECK Ramachandran: 1
PCK2 PROCHECK Chi-1 angle: 2
PCK3 PROCHECK H-bonds: 2
WCK1 WHAT_CHECK Packing: -2.166
WCK2 WHAT_CHECK Ramachandran: -1.552
WCK3 WHAT_CHECK Chi angles: -1.493
WCK4 WHAT_CHECK Backbone: 0.35

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).