On methods of measuring ceramic uselife: A revision of the uselife estimates of cooking vessels among the Kalinga, Philippines

The longevity of ceramic vessels in ethnographic contexts has been reported from several ceramic-using groups. Several methods have been used to derive estimates of the mean uselives of ceramic classes. Among them, the Kalinga Ethnoarchaeological Project employed a method based on a series of ceramic inventories since 1975. This inventory method recorded large number of pots, much more than any other previous studies, to ensure the representativeness of uselife estimates. Another data set of ceramic breakage collected by the project reveals that biases against short-lived pots were introduced by the inventory method. As a result, ceramic uselife estimated by the inventory method appears to be too long, and the revised estimates are similar to those observed in other contexts. This paper identifies the biases intrinsic to the inventory method and suggests revised uselife figures.