Table 3.

Summary statistics for actual and relative cusp base areas for the same observer

Cusp	Mean (S.E.B.1)	Mean (S.E.B.2)	Difference (mm)	Percentage error
Actual cusp base areas
Protocone	29.6	29.7	0.1	< 1
Paracone	23.6	23.5	0.1	< 1
Metacone	23.0	22.8	0.2	< 1
Hypocone	19.6	20.1	0.5	2.6
Relative cusp base areas
Protocone	30.9	30.9	0.0	0
Paracone	24.7	24.5	0.2	< 1
Metacone	24.1	23.8	0.3	1.2
Hypocone	20.3	20.8	0.5	2.5
Total cusp base area	95.8	96.1	0.3	< 1

n = 23, d.f. = 44.