Title: | Non-detects in qPCR data |
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Description: | Methods to model and impute non-detects in the results of qPCR experiments. |
Authors: | Matthew N. McCall <[email protected]>, Valeriia Sherina <[email protected]> |
Maintainer: | Valeriia Sherina <[email protected]> |
License: | GPL-3 |
Version: | 2.35.0 |
Built: | 2024-07-02 04:49:27 UTC |
Source: | https://github.com/bioc/nondetects |
A study of the effect of p53 and/or Ras mutations on gene expression. The third dataset is a comparison between four cell types – YAMC cells, mutant-p53 YAMC cells, activated-Ras YAMC cells, and p53/Ras double mutant YAMC cells. Three replicates were performed for the untransformed YAMC cells, and four replicates were performed for each of the other cell types.
data(nature2008)
data(nature2008)
A qPCRset object.
data(nature2008) show(nature2008)
data(nature2008) show(nature2008)
Two cell types – young adult mouse colon (YAMC) cells and mutant-p53/activated-Ras transformed YAMC cells – in combination with three treatments – untreated, sodium butyrate, or valproic acid. Four replicates were performed for each cell-type/treatment combination.
data(oncogene2013)
data(oncogene2013)
A qPCRset object.
data(oncogene2013) show(oncogene2013)
data(oncogene2013) show(oncogene2013)
This function models the missing data mechanism and uses an EM algorithm to impute the non-detect values in qPCR data.
qpcrImpute(object, dj=NULL, pyfit=NULL, groupVars=NULL, batch=NULL, tol=1, iterMax=100, outform=c("Single","Param","Multy"), vary_fit=TRUE, vary_model=TRUE, add_noise=TRUE, formula=NULL, numsam=5, linkglm = c("logit", "probit", "cloglog"))
qpcrImpute(object, dj=NULL, pyfit=NULL, groupVars=NULL, batch=NULL, tol=1, iterMax=100, outform=c("Single","Param","Multy"), vary_fit=TRUE, vary_model=TRUE, add_noise=TRUE, formula=NULL, numsam=5, linkglm = c("logit", "probit", "cloglog"))
object |
a qPCRset |
dj |
normalization values. If NULL, features with "control" in featureType(object) are used to normalize the data. If no control features are found, the data are not normalized. |
pyfit |
initial estimate of the relationship between the probability of a non-detect and average expression. If NULL, this relationship is estimated from the data. |
groupVars |
which columns in pData(object) should be used to determine replicate samples. If NULL, all columns are used. |
batch |
amatrix with control samples for each batch, if NULL, batch effect is not taken into account. |
tol |
likelihood convergence criterion of the EM algorithm. |
iterMax |
maximimum number of iterations of the EM algorithm. |
outform |
the form of the output requested.If "Single" performes a single imputation of missing values. If "Param" returnes estimated model parameters: mean and variance. If "Multy" performes a multiple imputation of missing values, and creats multiple data sets with imputed values. |
vary_fit |
if outform="Multy", includes the model uncertainty due to the logit of the probability of being missing. The default value is "TRUE". |
vary_model |
if outform="Multy", includes the model uncertainty due to the estimating mean of the data. The default value is "TRUE". |
add_noise |
if outform="Multy", introduses the variance component due to the random noise. The default value is "TRUE". |
formula |
specifies the model. |
numsam |
number of the datasets to be created if outform="Multy". The default value is 5. |
linkglm |
a link used for estimation of the missing data mechanism. |
The function returns a qPCRset object with non-detects replaced by their imputed values.
Valeriia Sherina
data(sagmb2011) tst <- qpcrImpute(sagmb2011, groupVars="sampleType", outform=c("Single"), batch=NULL, linkglm = c("logit"))
data(sagmb2011) tst <- qpcrImpute(sagmb2011, groupVars="sampleType", outform=c("Single"), batch=NULL, linkglm = c("logit"))
Cells transformed to malignancy by mutant p53 and activated Ras are perturbed with the aim of restoring gene expression to levels found in non-transformed parental cells via retrovirus-mediated re-expression of corresponding cDNAs or shRNA-dependent stable knock-down. The data contain 4-6 replicates for each perturbation, and each perturbation has a corresponding control sample in which only the vector has been added.
data(sagmb2011)
data(sagmb2011)
A qPCRset object.
data(sagmb2011) show(sagmb2011)
data(sagmb2011) show(sagmb2011)