Moderator: Ryan C. Thompson

gravatar for Ryan C. Thompson
Reputation:
7,260
Status:
Trusted
Location:
The Scripps Research Institute, La Jolla, CA
Website:
http://stackoverflow.c...
Twitter:
@DarwinAwdWinne
Last seen:
1 month, 3 weeks ago
Joined:
6 years, 5 months ago
Email:
r**@thompsonclan.org

Posts by Ryan C. Thompson

<prev • 820 results • page 1 of 82 • next >
0
votes
1
answer
105
views
1
answers
Comment: C: Making sense out of makeContrasts and using coefficents for contrasts
... I'll assume you meant `T5.LD.FW` instead of `T5.SP`. If so, you are testing the T6 difference against the mean of the T5 and T4 differences. That's not quite the same as what you're after. In any case, I find that these "difference of differences" contrasts are difficult to interpret without the con ...
written 9 weeks ago by Ryan C. Thompson ♦ 7.3k
0
votes
5
answers
173
views
5
answers
Answer: A: Random Effect in DESeq2
... To my knowledge, none of the negative binomial GLM-based packages (e.g. edgeR & DESeq2) support models with random effects. Limma is the only package I know of that does support RNA-seq analysis with random effects. It supports a model with any number of fixed effects and one factor as a random ...
written 9 weeks ago by Ryan C. Thompson ♦ 7.3k
0
votes
1
answer
105
views
1
answers
Comment: C: Making sense out of makeContrasts and using coefficents for contrasts
... What hypothesis are you attempting to test with this contrast? We can't tell you if your contrast is testing what you want to test unless you say what you want to test. In any case, the contrast you have written appears to be subtracting two terms from one term, which usually yields a nonsense con ...
written 9 weeks ago by Ryan C. Thompson ♦ 7.3k
2
votes
3
answers
158
views
3
answers
Answer: A: edgeR /DESeq2 normalization for differential expression in RNA-seq blood samples
... Aaron's answer adequately covers the theoretical reasons that the normalizations used in edgeR and DESeq2 are appropriate for data with variations in globin content, so I will just add that empirically, I have actually *used* edgeR on such a data set. Specifically, we were testing a custom globin bl ...
written 9 weeks ago by Ryan C. Thompson ♦ 7.3k
1
vote
2
answers
100
views
2
answers
Comment: C: Appropriate design formula for DESeq2 from principles
... This isn't an answer to your main question, but for an in-depth discussion of how design matrices are constructed from factors, you should have a read through the [vignette for the codingMatrices package](https://cran.r-project.org/web/packages/codingMatrices/vignettes/codingMatrices.pdf). You gener ...
written 10 weeks ago by Ryan C. Thompson ♦ 7.3k
1
vote
2
answers
139
views
2
answers
Comment: C: Order of contrasts.fit call (before or after eBayes)
... You can read the code of the functions to find out exactly what they are doing. I did that a while ago but I don't recall the exact details. I just remember that the rule I came up with was "always run `eBayes` on every fit", and I haven't had any trouble since. ...
written 10 weeks ago by Ryan C. Thompson ♦ 7.3k
0
votes
2
answers
139
views
2
answers
Comment: C: Order of contrasts.fit call (before or after eBayes)
... It's only necessary to call `eBayes` if you need the statistics that it calculates. This will almost always be the case for the contrast fit (since you want to call `topTable` on it), but sometimes you also want it for the regular fit as well. It normally only takes a second or two to run it, so I j ...
written 10 weeks ago by Ryan C. Thompson ♦ 7.3k
2
votes
2
answers
139
views
2
answers
Answer: A: Order of contrasts.fit call (before or after eBayes)
... I recommend saving the result of `contrasts.fit` as a separate object, so that you still have access to the original `lmFit` result as well. They both have their uses, as you have noted. Run `eBayes` on both of them. My typical workflow looks something like this: ``` fit <- lmFit(mat_data, desig ...
written 10 weeks ago by Ryan C. Thompson ♦ 7.3k
5
votes
2
answers
135
views
2
answers
Answer: A: LIMMA dupcor() function time issue.
... Looking at the code of duplicateCorrelation, the main time sink is the loop that runs mixedModel2Fit on each row of the input. So the time required should indeed be a linear function of the number of rows. However, the linear trend might break down if you are bumping up against hardware limits. The ...
written 10 weeks ago by Ryan C. Thompson ♦ 7.3k
0
votes
2
answers
231
views
2
answers
Comment: C: Use of pseudoalignment estimated counts as input to edgeR and Limma-Voom
... If you already have an alignment pipeline you're happy with, I wouldn't bother switching to another aligner. It's generally not going to make much of a difference. Just use featureCounts with your existing aligned BAM files. ...
written 10 weeks ago by Ryan C. Thompson ♦ 7.3k

Latest awards to Ryan C. Thompson

Good Answer 4 months ago, created an answer that was upvoted at least 5 times. For A: Batch correction in DESeq2
Popular Question 5 months ago, created a question with more than 1,000 views. For summarizeOverlaps using GRanges or bed file as reads?
Appreciated 5 months ago, created a post with more than 5 votes. For A: Finding DE genes from RNA-seq data
Teacher 6 months ago, created an answer with at least 3 up-votes. For A: Voom transformation from counts and normalization to negative values
Scholar 6 months ago, created an answer that has been accepted. For A: Limma validity for only hundreds of genes/metabolites
Appreciated 7 months ago, created a post with more than 5 votes. For A: RNA-seq Normalisation - normalise all samples in experiment or only the ones use
Teacher 7 months ago, created an answer with at least 3 up-votes. For A: Voom transformation from counts and normalization to negative values
Teacher 8 months ago, created an answer with at least 3 up-votes. For A: What's the relationship between "design" and "contrasts"?
Scholar 11 months ago, created an answer that has been accepted. For A: Limma validity for only hundreds of genes/metabolites
Teacher 11 months ago, created an answer with at least 3 up-votes. For A: RNA-seq Normalisation - normalise all samples in experiment or only the ones use
Popular Question 11 months ago, created a question with more than 1,000 views. For edgeR Quasi-likelihood with tagwise dispersion?
Teacher 11 months ago, created an answer with at least 3 up-votes. For A: What's the relationship between "design" and "contrasts"?
Popular Question 11 months ago, created a question with more than 1,000 views. For summarizeOverlaps using GRanges or bed file as reads?
Scholar 11 months ago, created an answer that has been accepted. For A: Limma validity for only hundreds of genes/metabolites
Teacher 11 months ago, created an answer with at least 3 up-votes. For A: What's the relationship between "design" and "contrasts"?
Scholar 22 months ago, created an answer that has been accepted. For A: How does the function model.matrix (to define experimental design) really works
Scholar 22 months ago, created an answer that has been accepted. For A: Duplicate Correlation with technical replicates
Scholar 22 months ago, created an answer that has been accepted. For A: RNA-seq Normalisation - normalise all samples in experiment or only the ones use
Teacher 22 months ago, created an answer with at least 3 up-votes. For A: RNA-seq Normalisation - normalise all samples in experiment or only the ones use
Teacher 22 months ago, created an answer with at least 3 up-votes. For A: How does the function model.matrix (to define experimental design) really works
Teacher 22 months ago, created an answer with at least 3 up-votes. For A: What's the relationship between "design" and "contrasts"?
Scholar 22 months ago, created an answer that has been accepted. For A: What's the relationship between "design" and "contrasts"?
Teacher 22 months ago, created an answer with at least 3 up-votes. For A: edger glmQLFit mix glmLRT
Appreciated 22 months ago, created a post with more than 5 votes. For A: RNA-seq Normalisation - normalise all samples in experiment or only the ones use
Popular Question 22 months ago, created a question with more than 1,000 views. For Rsubread::featureCounts extremely slow on some annotations
Content
Help
Access
Use of this site constitutes acceptance of our User Agreement and Privacy Policy.
Powered by Biostar version 16.09
Traffic: 155 users visited in the last hour