evalTypeIError: Evaluation of the type I error rate of enrichment methods
In waldronlab/GSEABenchmarkeR: Reproducible GSEA Benchmarking

evalTypeIError

R Documentation

Evaluation of the type I error rate of enrichment methods

Description

This function evaluates the type I error rate of selected methods for enrichment analysis when applied to one or more expression datasets.

Usage

evalTypeIError(
  methods,
  exp.list,
  gs,
  alpha = 0.05,
  ea.perm = 1000,
  tI.perm = 1000,
  perm.block.size = -1,
  summarize = TRUE,
  save2file = FALSE,
  out.dir = NULL,
  verbose = TRUE,
  ...
)

Arguments

`methods`	Methods for enrichment analysis. This can be either a character vector with method names chosen from `sbeaMethods` and `nbeaMethods`, a user-defined function implementing a method for enrichment analysis, or a named list, containing pre-defined and/or user-defined enrichment methods. See examples.
`exp.list`	Experiment list. A `list` of datasets, each being of class `SummarizedExperiment`.
`gs`	Gene sets, i.e. a list of character vectors of gene IDs.
`alpha`	Numeric. Statistical significance level. Defaults to 0.05.
`ea.perm`	Integer. Number of permutations of the sample group assignments during enrichment analysis. Defaults to 1000. Can also be an integer vector matching the length of 'methods' to assign different numbers of permutations for different methods.
`tI.perm`	Integer. Number of permutations of the sample group assignments during type I error rate evaluation. Defaults to 1000. Can also be an integer vector matching the length of `methods` to assign different numbers of permutations for different methods.
`perm.block.size`	Integer. When running in parallel, splits `tI.perm` into blocks of the indicated size. Defaults to -1, which indicates to not partition `tI.perm`.
`summarize`	Logical. If `TRUE` (default) applies `summary` to the vector of type I error rates across `tI.perm` permutations of the sample labels. Use `FALSE` to return the full vector of type I error rates.
`save2file`	Logical. Should results be saved to file for subsequent benchmarking? Defaults to `FALSE`.
`out.dir`	Character. Determines the output directory where results are saved to. Defaults to `NULL`, which then writes to `tools::R_user_dir("GSEABenchmarkeR")` in case `save2file` is set to `TRUE`.
`verbose`	Logical. Should progress be reported? Defaults to `TRUE`.
`...`	Additional arguments passed to the selected enrichment methods.

Value

A list with an entry for each method applied. Each method entry is a list with an entry for each dataset analyzed. Each dataset entry is either a summary (summarize=TRUE) or the full vector of type I error rates (summarize=FALSE) across tI.perm permutations of the sample labels.

Author(s)

Ludwig Geistlinger <Ludwig.Geistlinger@sph.cuny.edu>

Examples


    # loading three datasets from the GEO2KEGG compendium
    geo2kegg <- loadEData("geo2kegg", nr.datasets=3)

    # only considering the first 1000 probes for demonstration
    geo2kegg <- lapply(geo2kegg, function(d) d[1:1000,]) 

    # preprocessing and DE analysis for two of the datasets
    geo2kegg <- maPreproc(geo2kegg[2:3])
    geo2kegg <- runDE(geo2kegg)

    # getting a subset of human KEGG gene sets
    gs.file <- system.file("extdata", package="EnrichmentBrowser")
    gs.file <- file.path(gs.file, "hsa_kegg_gs.gmt") 
    kegg.gs <- EnrichmentBrowser::getGenesets(gs.file)

    # evaluating type I error rate of two methods on two datasets
    # NOTE: using a small number of permutations for demonstration;
    #       for a meaningful evaluation tI.perm should be >= 1000   
    res <- evalTypeIError(geo2kegg, methods=c("ora", 
             "camera"), gs=kegg.gs, ea.perm=0, tI.perm=3)

    # applying a user-defined enrichment method ...
    # ... or a mix of pre-defined and user-defined methods
    dummySBEA <- function(se, gs) 
    {
         sig.ps <- sample(seq(0, 0.05, length=1000), 5)
         nsig.ps <- sample(seq(0.1, 1, length=1000), length(gs)-5)
         ps <- sample(c(sig.ps, nsig.ps), length(gs))
         names(ps) <- names(gs)
         return(ps)
    }  

    methods <- list(camera = "camera", dummySBEA = dummySBEA)
    res <- evalTypeIError(methods, geo2kegg, gs=kegg.gs, tI.perm=3)

waldronlab/GSEABenchmarkeR documentation built on May 4, 2024, 1 a.m.