Principal component analysis in R

GC-MS retention index prediticon?

Hello experts, Does anyone know any free software about retention index prediction ?

08 August 2024 7,403 2 View

How to normalize and take the significance of the MTT OD values with 3 replicates for the same cell-line?

Hi, I have a question about normalizing the MTT OD values for doing the statistical analysis. So, if we have 3 different plates and we call them 3 different replicates, so, first we would...

07 August 2024 8,106 4 View

If we are using snowball sampling technique, how do we justify the true representativeness of the sample statistically? is there any statistical test?

Are there any statistical methods to justify your sampling technique using SPSS or AMOS?

05 August 2024 9,153 4 View

How to report results of Generalised Linear Mixed Models in a journal article?

Hi everyone, If you have written or come across any papers where Generalised Linear Mixed Models are used to examine intervention (e.g., in mental health) efficacy, could you please share the...

04 August 2024 4,130 4 View

Can anyone provide me with molecular docking softwares/ websites?

Molecular docking software/ websites?

02 August 2024 8,704 7 View

Why 3 replicates for most biological assays? Is it enough to examine the data fits normal distribution?

Just bounced on me. Before statistically analysing significant difference, shouldn't we see if data fits normal distribution first? Is 3 replicates enough to testify the hypothesis of normal...

31 July 2024 8,141 13 View

Which statistical test should we use?

N=6 Comparing pre and post test likert scale responses. Participants are mix of practicing & preservice teachers.

30 July 2024 7,233 4 View

I am working on my Master's thesis on the biogeography of the genus Ruagea and I would like to ask, could someone help me to check whether my result?

I created a file with my outgroup and ingroup species using Beauti, ran it in BEAST, viewed it in Tracer, and then used TreeAnnotator to create a file that I imported into RASP. Could someone...

28 July 2024 2,979 1 View

Is factor analysis with quantitative variables possible?

Good morning, I would like to conduct a factor analysis for my work at the municipal level on a panel datae with variables such as income per capita, unmployement rate, percentage employed in a...

25 July 2024 5,104 4 View

Which software tools are best for enhancing diagnostic accuracy in chest X-ray imaging using image reconstruction and neural networks?

I am reaching out to seek your valuable advice and recommendations regarding the best software tools to use for this research. Specifically, I am looking for software with a user-friendly...

22 July 2024 3,794 1 View

Moni Neradilek

PCA in R is covered in a classic book on S-Plus that is also relevant for R: Modern Applied Statistics with S-Plus by Venebles and Ripley. http://www.amazon.com/Modern-Applied-Statistics-Computing/dp/1441930086/ref=sr_1_2?ie=UTF8&qid=1328789554&sr=8-2

Various implementations of PCA and related methods (such as canonical correlations) are listed on the R website http://cran.r-project.org/, under "Task Views" > "Multivariate". There is an entire section on Principal components.

David Valentim Dias

Assuming you already known something about PCA...You can check vegan package vignette who can provide not so fast introduction to the topic.

Thiago Gomes Veríssimo

Ok, I will check this package, thank you. I can post here later my conclusions...

Alexander V Lebedev

There's even a very good video on youtube with step-by-step instructions:

http://www.youtube.com/watch?v=Heh7Nv4qimU

Novi Reandy Sasmita

you can download this file.

http://cran.r-project.org/web/packages/HSAUR/vignettes/Ch_principal_components_analysis.pdf