hill_acc_pq: Hill diversity accumulation curve for a phyloseq object...

In MiscMetabar: Miscellaneous Functions for Metabarcoding Analysis

Hill diversity accumulation curve for a phyloseq object (default: q = 1)

Description

Computes Hill diversity accumulation curves from a phyloseq object and returns a ggplot2 object.

Two types of curves are available:

• type = "individual" (default): individual-based (sequence-based) rarefaction/extrapolation curves via divent::accum_hill(), with one curve per sample (or per merged group).

• type = "sample": sample-based accumulation curve. Samples are pooled incrementally (over random permutations) and Hill diversity is computed at each step using divent::div_hill(). The x-axis represents the number of samples.

Usage

hill_acc_pq(
  physeq,
  q = 1,
  type = c("individual", "sample"),
  merge_sample_by = NULL,
  n_permutations = 100,
  conf_level = 0.95,
  ...
)

Arguments

physeq	(required) a phyloseq-class object obtained using the phyloseq package.
q	(numeric, default 1) Hill diversity order. Default is 1 (exponential of Shannon entropy), recommended for its robustness against rare and potentially erroneous sequences (Alberdi & Gilbert, 2019; Calderón-Sanou et al., 2019).
type	(character) Type of accumulation curve. Either "individual" (sequence-based, one curve per sample) or "sample" (sample-based, one curve for the whole dataset or per group).
merge_sample_by	(character or NULL) Variable name in sam_data used to group samples. Behaviour differs by type: type = "individual": samples are merged before computing curves (one curve per merged group, using merge_samples2()). type = "sample": samples are split by group and one accumulation curve is drawn per group, all on the same plot.
n_permutations	(integer, default 100) Number of random sample orderings used to compute the mean and confidence envelope for sample-based accumulation. Ignored when type = "individual".
conf_level	(numeric, default 0.95) Confidence level for the envelope around sample-based accumulation curves. Ignored when type = "individual".
...	Additional arguments passed to divent::accum_hill() (when type = "individual") or divent::div_hill() (when type = "sample").

Value

A ggplot2 object.

References

Alberdi, A., & Gilbert, M. T. P. (2019). A guide to the application of Hill numbers to DNA-based diversity analyses. Molecular Ecology Resources. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.1111/1755-0998.13014")}

Calderón-Sanou, I., Münkemüller, T., Boyer, F., Zinger, L., & Thuiller, W. (2019). From environmental DNA sequences to ecological conclusions: How strong is the influence of methodological choices? Journal of Biogeography, 47. \Sexpr[results=rd]{tools:::Rd_expr_doi("10.1111/jbi.13681")}

See Also

divent::accum_hill(), divent::div_hill(), hill_curves_pq()

Examples

## Not run: 
# Individual (sequence-based) accumulation curves
hill_acc_pq(rarefy_pq(data_fungi_mini, sample_size = 500, replace = TRUE),
  n_permutations = 3
) + no_legend()
hill_acc_pq(rarefy_pq(data_fungi_mini, sample_size = 500, replace = TRUE),
  n_permutations = 3,
  merge_sample_by = "Height"
)

# Sample-based accumulation curve
hill_acc_pq(data_fungi_mini, type = "sample", n_permutations = 3)
hill_acc_pq(data_fungi_mini,
  type = "sample", merge_sample_by = "Height",
  n_permutations = 3
)

## End(Not run)

MiscMetabar documentation built on June 8, 2026, 5:07 p.m.