correctBatchEffect {BEclear} | R Documentation |
This method combines most functions of the BEclear-package
to
one. The method performs the whole process of searching for batch effects and
automatically correct them for a matrix of beta values stemming from DNA
methylation data.
correctBatchEffect(data, samples, parallel=TRUE, cores=4, adjusted=TRUE, method="fdr", rowBlockSize=60, colBlockSize=60, epochs=50, outputFormat="RData", dir=getwd())
data |
any matrix filled with beta values, column names have to be sample_ids corresponding to the ids listed in "samples", row names have to be gene names. |
samples |
data frame with two columns, the first column has to contain the sample numbers, the second column has to contain the corresponding batch number. Colnames have to be named as "sample_id" and "batch_id". |
parallel |
should the calculation be done in parallel mode?
|
cores |
if running in parallel mode, define the number of cores used
for the calculation. |
adjusted |
should the p-values be adjusted or not, see "method" for available adjustment methods. |
method |
adjustment method for p-value adjustment (if TRUE), default
method is "false discovery rate adjustment", for other available methods
see the description of the used standard R package |
rowBlockSize |
the number of rows that is used in a block if the
function is run in parallel mode and/or not on the whole matrix. Set this,
and the "colBlockSize" parameter to 0 if you want to run the function on
the whole input matrix. See |
colBlockSize |
the number of columns that is used in a block if the
function is run in parallel mode and/or not on the whole matrix. Set this,
and the "rowBlockSize" parameter to 0 if you want to run the function on
the whole input matrix. See |
epochs |
the number of iterations used in the gradient descent
algorithm to predict the missing entries in the data matrix. See
|
outputFormat |
you can choose if the finally returned data matrix
should be saved as an .RData file or as a tab-delimited .txt file in the
specified directory. Allowed values are "RData" and "txt". See
|
dir |
set the path to a directory the predicted matrix should be stored. The current working directory is defined as default parameter. |
The function performs the whole process of searching for batch effects and
automatically correct them for a matrix of beta values stemming from DNA
methylation data. Thereby, the function is running most of the functions from
the BEclear-package
in a logical order.
First, median comparison values are calculated by the calcMedians
function, followed by the calculation of p-values by the
calcPvalues
function.
With the results from the median comparison and p-value calculation, a summary
data frame is build using the calcSummary
function, and a scoring
table is established by the calcScore
function.
Now, found entries from the summary are set to NA in the input matrix using the
clearBEgenes
function, then the BEclear
function is
used to predict the missing values and at the end, possibly existing wrongly
predicted entries (values lower than 0 or greater than 1) are corrected using
the replaceWrongValues
function.
A list containing the following fields (for detailed information look at the documentations of the corresponding functions):
medians |
A data.frame containing all median comparison values corresponding to the input matrix. |
pvalues |
A data.frame containing all p-values corresponding to the input matrix. |
summary |
The summarized results of the median comparison and p-value calculation. |
score.table |
A data.frame containing the number of found genes and a BEscore for every batch. |
cleared.data |
the input matrix with all values defined in the summary set to NA. |
predicted.data |
the input matrix after all previously NA values have been predicted. |
corrected.predicted.data |
the predicted matrix after the correction for wrongly predicted values. |
Y. Koren, R. Bell, C. Volinsky, Matrix factorization techniques for recommender systems, IEEE Computer, 42(8), p. 30-37, 2009, http://research.yahoo.com/pub/2859
E. Candes, B. Recht, Exact matrix completion via convex optimization, Communications of the ACM, 55(6), p. 111-119, 2012, http://doi.acm.org/10.114/2184319.2184343
calcMedians
calcPvalues
calcSummary
calcScore
clearBEgenes
BEclear
replaceWrongValues
## Shortly running example. For a more realistic example that takes ## some more time, run the same procedure with the full BEclearData ## dataset. ## Whole procedure that has to be done to use this function. ## Correct the example data for a batch effect data(BEclearData) ex.data <- ex.data[31:90,7:26] ex.samples <- ex.samples[7:26,] # Note that row- and block sizes are just set to 10 to get a short runtime. To # use these parameters, either use the default values or please note the # description in the details section of \code{\link{BEclear}} result <- correctBatchEffect(data=ex.data, samples=ex.samples, parallel=TRUE, cores=4, adjusted=TRUE, method="fdr", rowBlockSize=10, colBlockSize=10, epochs=50, outputFormat="RData", dir=getwd()) # Unlist variables medians <- result$medians pvals <- result$pvals summary <- result$summary score <- result$score.table cleared <- result$clearedData predicted <- result$predictedData corrected <- result$correctedPredictedData