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jackstraw (version 1.3.1)

jackstraw_cluster: Jackstraw for the User-Defined Clustering Algorithm

Description

Test the cluster membership using a user-defined clustering algorithm

Usage

jackstraw_cluster(
  dat,
  k,
  cluster = NULL,
  centers = NULL,
  algorithm = function(x, centers) kmeans(x, centers, ...),
  s = 1,
  B = 1000,
  center = TRUE,
  noise = NULL,
  covariate = NULL,
  verbose = FALSE,
  seed = NULL,
  ...
)

Arguments

dat

a data matrix with m rows as variables and n columns as observations.

k

a number of clusters.

cluster

a vector of cluster assignments.

centers

a matrix of all cluster centers.

algorithm

a clustering algorithm to use, where an output must include `cluster` and `centers`. For exact specification, see kmeans.

s

a number of ``synthetic'' null variables. Out of m variables, s variables are independently permuted.

B

a number of resampling iterations.

center

a logical specifying to center the rows. By default, TRUE.

noise

specify a parametric distribution to generate a noise term. If NULL, a non-parametric jackstraw test is performed.

covariate

a model matrix of covariates with n observations. Must include an intercept in the first column.

verbose

a logical specifying to print the computational progress. By default, FALSE.

seed

a seed for the random number generator.

...

optional arguments to control the clustering algorithm.

Value

jackstraw_cluster returns a list consisting of

F.obs

m observed F statistics between variables and cluster centers.

F.null

F null statistics between null variables and cluster centers, from the jackstraw method.

p.F

m p-values of membership.

Details

The clustering algorithms assign m rows into K clusters. This function enable statistical evaluation if the cluster membership is correctly assigned. Each of m p-values refers to the statistical test of that row with regard to its assigned cluster. Its resampling strategy accounts for the over-fitting characteristics due to direct computation of clusters from the observed data and protects against an anti-conservative bias.

The user is expected to explore the data with a given clustering algorithm and determine the number of clusters k. Furthermore, provide cluster and centers as given by applying algorithm onto dat. The rows of centers correspond to k clusters, as well as available levels in cluster. This function allows you to specify a parametric distribution of a noise term. It is an experimental feature.

References

Chung and Storey (2015) Statistical significance of variables driving systematic variation in high-dimensional data. Bioinformatics, 31(4): 545-554 https://academic.oup.com/bioinformatics/article/31/4/545/2748186

Chung (2020) Statistical significance of cluster membership for unsupervised evaluation of cell identities https://academic.oup.com/bioinformatics/article/36/10/3107/5788523