BchronDensityFast {Bchron} | R Documentation |

## Non-parametric phase model (faster version)

### Description

This function runs a non-parametric phase model on 14C and non-14C ages via Gaussian Mixture density estimation through the mclust package

### Usage

```
BchronDensityFast(
ages,
ageSds,
calCurves,
pathToCalCurves = system.file("data", package = "Bchron"),
dfs = rep(100, length(ages)),
samples = 2000,
G = 30
)
```

### Arguments

`ages` |
A vector of ages (most likely 14C) |

`ageSds` |
A vector of 1-sigma values for the ages given above |

`calCurves` |
A vector of values containing either |

`pathToCalCurves` |
File path to where the calibration curves are located. Defaults to the system directory where the 3 standard calibration curves are stored. |

`dfs` |
Degrees-of-freedom values for the t-distribution associated with the calibration calculation. A large value indicates Gaussian distributions assumed for the 14C ages |

`samples` |
Number of samples of calibrated dates required |

`G` |
Number of Gaussian mixture components |

### Details

This is a faster approximate version of `BchronDensity`

that uses the `densityMclust`

function to compute the Gaussian mixtures for a set of calibrated ages. The method is an approximation as it does not fit a fully Bayesian model as `BchronDensity`

does. It is designed to be a probabilistic version of the Oxcal SUM command which takes calibrated ages and sums the probability distributions with the aim of estimating activity through age as a proxy.

### Value

An object of class `BchronDensityRunFast`

with the following components:

`out` |
The output from the run of |

`calAges` |
The calibrated ages from the |

### See Also

`Bchronology`

, `BchronCalibrate`

, `BchronRSL`

, `BchronDensity`

for a slower exact version of this function

### Examples

```
# Read in some data from Sluggan Moss
data(Sluggan)
# Run the model
SlugDensFast <- with(
Sluggan,
BchronDensityFast(
ages = ages,
ageSds = ageSds,
calCurves = calCurves
)
)
# plot it
plot(SlugDensFast)
```

*Bchron*version 4.7.6 Index]