Age model estimation in paleoclimatic research: Fuzzy regression and radiocarbon uncertainties

A fuzzy linear regression-based method to relate the depth and age of sediment layers is described. Because algae, moss or local plants respond to climatic change, the age and depth of sediment layers are interrelated variables but the link between them is often imprecise. In most cases, due to the limited number of layers in a core (i.e., small number of data points), estimation of the slope and uncertainties in classical regression analysis does not take into account the uncertainties in radiocarbon dating. Here, fuzzy linear regression, which may be applied even to a very small data set, is utilized. The method, illustrated through a practical example, with eight data points, appears to be a promising tool in stratigraphic studies to link sediment age to layer depth and takes into account uncertainties from radiocarbon dating.