Table 3. Classification success of cross-validation for cockle Cerastoderma edule based on trace elemental composition in the shell from five locations within Mira (M1 and M2), Espinheiro (E1 and E2) and Ílhavo (I) Channels in Ria de Aveiro, Portugal.

	Predicted Locations					Total per location	% correct (location)
	M1	M2	E1	E2	I
Original Area
M1	10					10	100
M2		10				10	100
E1			8	2		10	80
E2			2	8		10	80
I					10	10	100
Average classification success							92