Section: Application Domains
Archaeology
We have been working since 2011 on the construction of new Bayesian approach for chronological modeling: this is an important issue in archaeology and paleo-environmental sciences. The archaeologists base their interpretations on a wide range of sources of information. A priori knowledge about the parameters of the model is often available, and so it should be considered along with the model and the data. This motivates the Bayesian choice.
In our case the data are the measurements
Tools for Constructing Chronologies
The aim is to provide probabilistic estimation of a chronology; a crucial aspect is to obtain a robust approach with respect to outliers due to the sampling in the field or the measurement process in the laboratory.
The solution proposed in [7], [6] is based on the
"event model'. We define the Event as the date
where
-
represents the experimental error provided by the laboratory and the calibration step. -
represents the irreducible error between and due to sampling problems external to the laboratory
In [7], [6], we show the ability of the variance
To enrich the chronological modelling, we wish to incorporate archaeological “phases”. Contrary to an “event”, a phase suggests duration. The objective is then to estimate the parameters that characterize the phase (beginning /end/duration), and then to develop Bayesian tests on the duration of the phase or the existence of a gap (hiatus) between two phases.
Calibration
The dating processes provide measurements, which are converted into calendar dates using calibration reference curves. We plan to explore issues related to calibration for different dating methods.
Optically stimulated luminescence (OSL) dating is a quantitative dating method to determine the time of last exposure of sand and silt to sunlight. Our aim is to complete the model constructed in [2] in order to obtain an OSL age determination.
We generally observe a overestimation of the age of a sample by OSL dating. This can be explaining by an insufficient resetting of the optically stimulated luminescence signal prior to sediment deposition. Therefore detection of so-called poor bleaching is of prime importance in OSL dating.