model.test.wrapper: Model test wrapper

View source: R/model.test.wrapper.R

model.test.wrapperR Documentation

Model test wrapper

Description

A wrapper function for model.test to perform a model fitting analysis on disparity through time data.

Usage

model.test.wrapper(
  data,
  model,
  pool.variance = NULL,
  time.split = NULL,
  fixed.optima = FALSE,
  control.list = list(fnscale = -1),
  verbose = TRUE,
  sim = 1000,
  plot.sim = TRUE,
  col.sim,
  col.obs = "hotpink",
  lwd.obs = 2,
  show.p = FALSE,
  cex.p,
  legend = FALSE,
  ...
)

Arguments

data

A dispRity object used to test models of evolution through time.

model

The model(s) of evolution to allow for changes in disparity-through-time using a homogenous or hetergenous model, either using a single input or a list containing different models (see list in model.test). If a vector with multiple modes is supplied then the model will test for shifts in modes at the time supplied by time.split.

pool.variance

If NULL (default) the difference in variances will be calculated using bartlett.test of equal variances. If there is no significant difference among variances, then variance in samples will be pooled and the same variance will be used for all samples. A significance difference will not pool variances and the original variance will be used for model-testing. If argument TRUE or FALSE are used, Bartlett's test will be ignored and the analyses will use the user-set pooling of variances.

time.split

The age of the change in mode (numeric). The age is measured in positive units as the time before the most recent sample, and multiple ages can be supplied in a vector. If no age is supplied for models then all possible time shifts are fit in the model, and the highest likelihood model is returned. Note this only applies to heterogenous models (See Details).

fixed.optima

A logical value, whether to use an estimated optimum value in OU models (FALSE - default), or whether to set the OU optimum to the ancestral value (TRUE).

control.list

A list of fine-tune control inputs for the optim function.

verbose

logical, whether to display the model results as computed (TRUE - default).

sim

The number of separate simulations (default = 1000).

plot.sim

Logical. If TRUE (default) the plots of the simulated and observed disparity are returned for all models.

col.sim

Colour options used for the plotting of simulated values. See plot.dispRity for more details. If missing, the default colours c("black", "lightgrey", "grey") are used.

col.obs

Colour of the observed data on the plot. Default colour is "hotpink"

lwd.obs

Line width of the observed value.

show.p

Logical, when plot.sim = TRUE, whether to display the p-value of rank envelope tests (TRUE) or not (FALSE - default).

cex.p

A numerical value for the the font size of the displayed p-value (if show.p = TRUE). If missing, the value is set to 1.

legend

Logical, when plot.sim = TRUE, whether to display the legend in the first panel (TRUE) or not (FALSE - default).

...

Any additional arguments to be passed to plot.dispRity or summary.dispRity.

Details

This function gives the relative fit of model.test output using log-likelihood and AICc values, as well as the Rank Envelope Test significance to elucidate if empirical data is significantly different to simulated data modelled using the estimated model parameters from model.test.sim. This is equivalent to running test <- model.test.sim(sim = 1000, model = model.test(data, model)); summary(test) ; plot(test) ; plot(data, add = TRUE).

DISCLAIMER: this function is working properly (i.e. it does what it is supposed to do), however, the interpretation of the results has not yet been thought through, discussed and peer-reviewed (what does a Brownian motion like disparity curve means biologically?).

Value

A matrix with the relative fit, parameter values, and Rank Envelope test p values for each model, and a plot of simulated data from each model alongside observed data for each model if plot.sim is TRUE

Author(s)

Mark N Puttick and Thomas Guillerme

References

Blomberg SP, Garland T Jr, & Ives AR. 2003. Testing for phylogenetic signal in comparative data: behavioral traits are more labile. Evolution. 57, 717-745.

Hansen TF. 1997. Stabilizing selection and the comparative analysis of adaptation. Evolution. 51, 1341-1351.

Harmon LJ, et al. 2010. Early bursts of body size and shape evolution are rare in comparative data. 64, 2385-2396.

Hunt G. 2006. Fitting and comparing models of phyletic evolution: random walks and beyond. Paleobiology. 32, 578-601. DOI: 10.1666/05070.1.

Hunt G, Hopkins MJ & Lidgard S. 2015. Simple versus complex models of trait evolution and stasis as a response to environmental change. Proceedings of the National Academy of Sciences. 112, 4885-4890. DOI: 10.1073/pnas.1403662111

Felsenstein J. 1973. Maximum-likelihood estimation of evolutionary trees from continuous characters. American Journal of Human Genetics. 25, 471-492.

Felsenstein J. 1985. Phylogenies and the comparative method. The American Naturalist. 51, 1-15.

Murrell DJ. 2018. A global envelope test to detect non-random bursts of trait evolution. Methods in Ecology and Evolution. DOI: 10.1111/2041-210X.13006

See Also

model.test, model.test.sim, summary.dispRity and plot.dispRity

Examples


## Not run: 
## Mammal disparity through time
data(BeckLee_disparity)

## The models to be fit to disparity data
models <- list("BM", "OU", "multi.OU", "Trend")

## test all models, and assess the significance of simulated data
## against the empirical distribution for each
model.test.wrapper(data = BeckLee_disparity, model = models, fixed.optima = TRUE,
                   time.split = 66, show.p = TRUE)

## End(Not run)


dispRity documentation built on May 29, 2024, 9:40 a.m.