dba.report: Generate a report for a differential binding affinity...

In DiffBind: Differential Binding Analysis of ChIP-Seq Peak Data

Description

Generates a report for a differential binding affinity analysis

Usage

dba.report(DBA, contrast, method=DBA$config$AnalysisMethod, 
           th=DBA$config$th, bUsePval=DBA$config$bUsePval, 
           fold=0, bNormalized=TRUE, bFlip=FALSE, precision,
           bCalled=FALSE, bCounts=FALSE, bCalledDetail=FALSE,
           bDB, bNotDB, bAll=TRUE, bGain=FALSE, bLoss=FALSE,
           file,initString=DBA$config$reportInit,ext='csv',DataType=DBA$config$DataType) 

Arguments

DBA	DBA object. A differential binding affinity analysis needs to have been previously carried out (see dba.analyze).

contrast	contrast number to report on. When generating a report-based DBA object, this can be a vector of contrast numbers. If missing, defaults to first contrast for reports, and all contrasts when generating a report-based DBA object. See dba.show(DBA, bContrast=T) to get contrast numbers.
method	method used for analysis: DBA_DESEQ2 DBA_DESEQ2_BLOCK DBA_EDGER DBA_EDGER_BLOCK When generating a report-based DBA object (see bDB and bNotDB parameters below), a vector of methods may be supplied, including the shortcuts DBA_ALL_METHODS DBA_ALL_BLOCK DBA_ALL_METHODS_BLOCK
th	significance threshold; all sites with FDR (or p-values, see bUsePval) less than or equal to this value will be included in the report. A value of 1 will include all binding sites in the report.
bUsePval	logical indicating whether to use FDR (FALSE) or p-value (TRUE) for thresholding.
fold	only sites with an absolute log Fold value greater than equal to this will be included in the report.
bNormalized	logical indicating that normalized data (using normalization factors computed b y differential analysis method) should be reported. FALSE uses raw count data.
bFlip	logical indicating that order of groups in contrast should be "flipped", allowing control of which sample group will have positive and which will have negative fold changes.
precision	If present, alters the default precision for the Concentration, Fold, p-value, and FDR values in the returned report. A value of 0 indicates maximum precision. Otherwise, it should be a 2-value vector. The first value controls how many digits to the right of the decimal to include for concentration and fold values. These second value control how many digits to the right of the decimal to include for the p-value and FDRs. Default is precision=2:3, unless DataType=DBA_DATA_SUMMARIZED_EXPERIMENT, in which case the default is 0 (full precision).
bCalled	logical indicating that peak caller status should be included. This will add a column for each group, each indicating the number of samples in the group identified as a peak in the original peaksets. Note that this option is only available if the consensus peakset was calculated by dba.count; if a consensus peakset was passed in explicitly using the peaks parameter, original peak origins are lost.
bCounts	logical indicating that count data for individual samples should be reported as well as group statistics. Columns are added for each sample in the first group, followed by columns for each sample in the second group.
bCalledDetail	logical indicating that peak caller status should be included for each sample (if available). Columns are added for each sample in the first group, followed by columns for each sample in the second group.
bDB	logical indicating that a report-based DBA object should be generated, and that it should include Differentially Bound (DB) sites (respecting the th, bUsePval, and fold parameters).
bNotDB	logical indicating that a report-based DBA object should be generated, and that it should include non-Differentially Bound (non-DB) sites (respecting the th, bUsePval, and fold parameters).
bAll	logical indicating that a report-based DBA object should be generated, and that it should include peaksets combining peaks with both positive and negative fold changes.
bGain	logical indicating that a report-based DBA object should be generated, and that it should include peaksets with only positive fold changes.
bLoss	logical indicating that a report-based DBA object should be generated, and that it should include peaksets with only negative fold changes.
file	if present, also save the report to a comma separated value (csv) file, using this filename.
initString	if saving to a file, pre-pend this string to the filename.
ext	if saving to a file, append this extension to the filename.
DataType	The class of object for returned report: DBA_DATA_GRANGES DBA_DATA_RANGEDDATA DBA_DATA_FRAME If set to DBA_DATA_SUMMARIZED_EXPERIMENT, the result will be a SummarizedExperiment object, with all the count data and sample metadata for the experiment. The contrast statistics will be included as metadata columns in the rowData of the object. Can be set as default behavior by setting DBA$config$DataType.

Value

if neither bDB or bNotDB is set to TRUE, a report dataframe or GRanges object is returned, with a row for each binding site within the thresholding parameters, and the following columns:

Chr	Chromosome of binding site
Start	Starting base position of binding site
End	End base position of binding site
Conc	Concentration – mean (log) reads across all samples in both groups
Conc_group1	Group 1 Concentration – mean (log) reads across all samples first group
Conc_group2	Group 2 Concentration – mean (log) reads across all samples in second group
Fold	Fold difference – mean fold difference of binding affinity of group 1 over group 2 (Conc1 - Conc2). Absolute value indicates magnitude of the difference, and sign indicates which one is bound with higher affinity, with a positive value indicating higher affinity in the first group
p-value	p-value calculation – statistic indicating significance of difference (likelihood difference is not attributable to chance)
FDR	adjusted p-value calculation – p-value subjected to multiple-testing correction

If bCalled is TRUE and caller status is available, two more columns will follow:

Called1	Number of samples in group 1 that identified this binding site as a peak
Called2	Number of samples in group 2 that identified this binding site as a peak

If bCounts is TRUE, a column will be present for each sample in group 1, followed by each sample in group 2, if present. The SampleID will be used as the column header. This column contains the read counts for the sample.

If bCalledDetail is TRUE, a column will be present for each sample in group 1, followed by each sample in group 2, if present. The SampleID will be used as the column header. This column contains a "+" to indicate for which sites the sample was called as a peak, and a "-" if it was not so identified.

If bDB or bNotDB is set to TRUE, a special DBA object is returned, containing peaksets based on sites determined to be differentially bound (or not) as specified using the bDB, bNotDB, bGain, bLoss, and bAll parameters. In this DBA object, the Tissue value will specify the direction of the change (Gain for positive fold changes, Loss for negative fold changes, and All for any fold change). The Factor value specifies if the peaks are differentially bound (DB) or not (!DB). The Condition value specifies the analysis method (e.g. edgeR), and the Treatment value is blank for unblocked analyses and set to block for blocked analyses.

Author(s)

Rory Stark

See Also

dba.analyze

Examples

data(tamoxifen_analysis)

#Retrieve DB sites with FDR <  0.05
tamoxifen.DB <- dba.report(tamoxifen)
tamoxifen.DB

#Retrieve DB sites with p-value <  0.05 and Fold > 2
tamoxifen.DB <- dba.report(tamoxifen, th=.05, bUsePval=TRUE, fold=2)
tamoxifen.DB

#Retrieve all sites with confidence stats
# and how many times each site was identified as a peak
tamoxifen.DB <- dba.report(tamoxifen, th=1, bCalled=TRUE)
tamoxifen.DB

#Retrieve all sites with confidence stats and normalized counts
tamoxifen.DB <- dba.report(tamoxifen, th=1, bCounts=TRUE)
tamoxifen.DB

#Retrieve all sites with confidence stats and raw counts
tamoxifen.DB <- dba.report(tamoxifen, th=1, bCounts=TRUE,bNormalized=FALSE)
tamoxifen.DB

#Retrieve report as a SummarizedObject
tamoxifen.sset <- dba.report(tamoxifen, DataType=DBA_DATA_SUMMARIZED_EXPERIMENT)
tamoxifen.sset

#Retrieve report-based DBA object
data(tamoxifen_analysis)
tamoxifen <- dba.analyze(tamoxifen,method=DBA_ALL_METHODS)
tamoxifen.DB <- dba.report(tamoxifen,method=c(DBA_EDGER,DBA_DESEQ2),
                          bDB=TRUE)
tamoxifen.DB
dba.plotVenn(tamoxifen.DB,1:2)

DiffBind documentation built on March 24, 2021, 6 p.m.