Apply the model after Fuchs & Lang (2001) to a given De distribution

This function applies the method according to Fuchs & Lang (2001) for heterogeneously bleached samples with a given coefficient of variation threshold.

Usage

calc_FuchsLang2001(data, cvThreshold = 5, startDeValue = 1, plot = TRUE, ...)

Arguments

data: RLum.Results or data.frame (required): for data.frame: two columns with De (data[,1]) and De error (values[,2])
cvThreshold: numeric (with default): coefficient of variation in percent, as threshold for the method, e.g. cvThreshold = 3. See details .
startDeValue: numeric (with default): number of the first aliquot that is used for the calculations
plot: logical (with default): enable/disable the plot output.
...: further arguments and graphical parameters passed to plot

Value

Returns a plot (optional) and terminal output. In addition an RLum.Results object is returned containing the following elements:

summary: data.frame summary of all relevant model results.
data: data.frame original input data
args: list used arguments
call: call the function call
usedDeValues: data.frame containing the used values for the calculation

Details

Used values

If the coefficient of variation (c[v]) of the first two values is larger than the threshold c[v_threshold], the first value is skipped. Use the startDeValue argument to define a start value for calculation (e.g. 2nd or 3rd value).

Basic steps of the approach

Estimate natural relative variation of the sample using a dose recovery test
Sort the input values in ascending order
Calculate a running mean, starting with the lowermost two values and add values iteratively.
Stop if the calculated c[v] exceeds the specified cvThreshold

Note

Please consider the requirements and the constraints of this method (see Fuchs & Lang, 2001)

Function version

0.4.1

How to cite

Kreutzer, S., Burow, C., 2025. calc_FuchsLang2001(): Apply the model after Fuchs & Lang (2001) to a given De distribution. Function version 0.4.1. In: Kreutzer, S., Burow, C., Dietze, M., Fuchs, M.C., Schmidt, C., Fischer, M., Friedrich, J., Mercier, N., Philippe, A., Riedesel, S., Autzen, M., Mittelstrass, D., Gray, H.J., Galharret, J., Colombo, M., Steinbuch, L., Boer, A.d., 2025. Luminescence: Comprehensive Luminescence Dating Data Analysis. R package version 1.1.1. https://r-lum.github.io/Luminescence/

References

Fuchs, M. & Lang, A., 2001. OSL dating of coarse-grain fluvial quartz using single-aliquot protocols on sediments from NE Peloponnese, Greece. In: Quaternary Science Reviews 20, 783-787.

Fuchs, M. & Wagner, G.A., 2003. Recognition of insufficient bleaching by small aliquots of quartz for reconstructing soil erosion in Greece. Quaternary Science Reviews 22, 1161-1167.

Author

Sebastian Kreutzer, Institute of Geography, Heidelberg University (Germany)
Christoph Burow, University of Cologne (Germany) , RLum Developer Team

Examples

## load example data
data(ExampleData.DeValues, envir = environment())

## calculate De according to Fuchs & Lang (2001)
temp<- calc_FuchsLang2001(ExampleData.DeValues$BT998, cvThreshold = 5)
#> 
#> [calc_FuchsLang2001]
#> 
#> ----------- meta data --------------
#>  cvThreshold:             5 %
#>  used values:             22
#> ----------- dose estimate ----------
#>  mean:                    2866.11
#>  sd:                      157.35
#>  weighted mean:           2846.66
#>  weighted sd:             20.58
#> ------------------------------------
#>