Porovnat metody

	Amino Acid Racemization	Bayesian Chronological Modeling
Obor	Archeologie	Archeologie
Rodina	Regression model	Regression model
Rok vzniku	1997	2009
Tvůrce	Reviewed for archaeology by Beverly Johnson and Gifford Miller	Christopher Bronk Ramsey (OxCal); Caitlin Buck and colleagues (Bayesian framework)
Typ	Chemical kinetic dating clock based on the racemization of amino acids in biogenic materials	Bayesian statistical model combining dates with prior archaeological information
Původní zdroj	Johnson, B. J., & Miller, G. H. (1997). Archaeological Applications of Amino Acid Racemization. Archaeometry, 39(2), 265-287.	Bronk Ramsey, C. (2009). Bayesian Analysis of Radiocarbon Dates. Radiocarbon, 51(1), 337-360.
Další názvy	AAR Dating, Amino Acid Geochronology, Amino Acid Epimerization, D/L Ratio Dating	Bayesian Radiocarbon Modeling, OxCal Bayesian Chronology, Bayesian Phase Modeling, Chronological Bayesian Modeling
Příbuzné	3	3
Shrnutí	Amino acid racemization (AAR) dating estimates the age of biogenic materials such as mollusc shell, ostrich eggshell, bone, and teeth from the slow chemical conversion of amino acids from one mirror-image form to the other after an organism dies. Living tissue builds proteins almost entirely from left-handed (L) amino acids, but after death these gradually interconvert toward an equilibrium mixture of left- and right-handed (D) forms, so the measured ratio of D to L rises predictably with time. Because the reaction is a temperature-dependent chemical process rather than a radioactive decay, AAR is fundamentally a kinetic clock that must be calibrated against an independently dated reference and corrected for the sample's thermal history. Reviewed for archaeology by Johnson and Miller and covered as a standard chronometric tool in Renfrew and Bahn's textbook, it offers a rapid, inexpensive way to date or correlate deposits across the Quaternary, well beyond the radiocarbon range.	Bayesian chronological modeling refines archaeological chronologies by combining the calibrated probability distributions of individual radiocarbon dates with prior archaeological knowledge — most importantly the stratigraphic order of samples and their grouping into phases — within a single Bayesian model. Rather than treating each date in isolation, the method asks what calendar ages are jointly consistent with all the dates and all the ordering constraints at once, and returns sharpened posterior distributions for each date plus estimates of the start, end, and duration of phases and the timing of events. Formalized by Caitlin Buck and colleagues and made widely usable through Christopher Bronk Ramsey's OxCal software, with the international IntCal calibration curve as input, it has become the standard framework for high-precision archaeological dating.