Displaying 20 results from an estimated 10000 matches similar to: "(no subject)"
2005 May 12
0
Multidimensional Scaling with pairwise Fst
I want to create a MDS plot with pairwise Fst values derived from a 
population genetics project.  My Fst values are in a tab-delimited file 
(lower triangle only) that I view with Excel.  When I use the cmdscale 
command I get the message:
Error in cmdscale(x) : Distances must be result of dist or a square 
matrix
In addition: Warning messages:
1: "^" not meaningful for factors in:
2011 Jul 28
3
R
Good afternoon.
I am a master student in University of Porto in Portugal. At this moment I’m
starting to use R, so I have some doubts.
The aim of my analysis is:  calculate a pairwise FST matrix from fasta file
and creat a principal component analyses with adegenet package (I use seqinr
and ape package to read this file, then I convert this file into a genind
object with DNA2genind function
2018 Mar 15
3
stats 'dist' euclidean distance calculation
Hello,
I am working with a matrix of multilocus genotypes for ~180 individual snail samples, with substantial missing data. I am trying to calculate the pairwise genetic distance between individuals using the stats package 'dist' function, using euclidean distance. I took a subset of this dataset (3 samples x 3 loci) to test how euclidean distance is calculated:
3x3 subset used
         
2010 Jan 06
1
positive log likelihood and BIC values from mCLUST analysis
My question is with respect to mCLUST and the values of BIC and log
likelihood. The relevant part of my R script is:
######################### BEGIN MDS ANALYSIS #########################
#load data
 data <- read.table("Ecoli33_Barry.dis", header = TRUE, row.names = 1)
 #perform MDS Scaling
 mds <- metaMDS(data, k = Dimensions, trymax = 20, autotransform =TRUE,
noshare = 0.1,
2006 Mar 12
0
New version of the LDheatmap package
Version 0.2 of the package LDheatmap is now on CRAN. The main function 
LDheatmap produces a graphical display, as a heat map, of measures of 
pairwise linkage disequilibria between SNPs. Users may optionally 
include the physical locations or genetic map distances of each SNP on 
the plot.
The revisions to the package are aimed at improving the user's ability 
to modify and annotate the
2007 Sep 27
2
create data frame(s) from a list with different numbers of rows
# Hello,
# I have a list with 6 categories and with different numbers of rows.
# I would like to change each of them into a unique data frame in order to
match
# values with other data frames and perform some calculations.
# Or I could make each category or list element have the same number of rows
and create one large data.frame.
# below is a creation of a sample list
# I apologize for the
2004 Nov 16
1
Pairwise Distances -- How to vectorize the loop
R-List,
I'm trying to compute pairwise distances among pairs of observations, 
which each pair containing data from 2 groups. There are more than 
100000 unique pairs. I have programmed a distance function that has 
three parameters, a vector of covariates from the ith observation in 
Group 1, a vector of covarites from the jth observation in Group 2, and 
a weighting matrix.
I have used
2013 Jan 18
1
scaling of nonbinROC penalties
Dear R Helpers
I am having difficulty understanding how to use the penalty matrix for the nomROC function in package 'nonbinROC'.
The documentation says that the values of the penalty matrix code the 
penalty function L[i,j] in which 0 <= L[i,j] <= 1 for
j > i. It gives an example that if we have an ordered response with 4 categories, then we might wish to penalise larger
2007 May 30
3
sizing and saving graphics in R
Dear R wizards,
I am seeking advice on graphics in R.  Specifically, how to manipulate  
the size and save a plot I have produced using the LDheatmap library.   
I confess I am relatively new to graphics in R, but I would greatly  
appreciate any suggestions you may have.
LDheatmap produces a coloured triangular matrix of pairwise  
associations between 600 genetic markers in my dataset. 
2010 Jul 19
2
replacing elements of distance matrix
Hi! I am trying to implement non-bipartite matching. I have around 500 sites
which can be clustered by 10 regions. I am able to calculate pairwise
Mahalanobis distances between sites (thanks to another post in the forum).
However, I want to constrain my match to sites within the same region. Thus
I want to replace elements of the distance matrix with a high value, say
999999, for sites not of the
2010 Jan 19
1
restricted permutations in permtest()?
Hallo List,
I'm trying to implemement a restricted permutation scheme in permutest(). More
precisely I have dependence in my data that should be allowed for in the
permutation - I simulated the problem in the example of the vegan documentation
p.24:
library(vegan)
data(varespec)
## Bray-Curtis distances between samples
dis <- vegdist(varespec)
## First 16 sites grazed, remaining 8 sites
2011 May 31
0
Mantel - like analysis
Hello,
I've used mantel tests a fair bit for standard genetic/geographic/landscape
analyses.  I realize it involves permutations of rows and columns in the
matrix to obtain correlation coefficients.
However, for a certain question, I am interested in populations that are
nearest neighbours to each other, and identifying factors that affect
genetic distance between them.  So because of
2010 Oct 21
1
SVM classification based on pairwise distance matrix
Dear all,
I am exploring the possibilities for automated classification of my 
data. I have successfully used KNN, but was thinking about looking at 
SVM (which I did nto use before).
I have a pairwise distance matrix of training observations which are 
classified in set classes, and a distance matrix of new observations to 
the  training ones.
Is it possible to use distance matrices for SVM, and
2012 Jul 30
0
pairwise comparisons in accordance with regression fit
Hello,
I have a unconventional question arising from my current master thesis on
regression modeling. Suppose we have fitted a (linear) relationship between
a dependent variable y and an independent variable x. Now we choose two
points on the x-axis, i.e. according to percentiles x10 and x90. These two
points are chosen to select the data points for two groups in order to
perform pairwise
2008 Nov 10
2
how to convert indvidual pairwise distances to matrix
Hello,
I am trying to convert list of pairwise distances to a distance matrix for
spatial analysis (kriging). For instance, I have something like this for
each pair pf points, and I want to convert it to a matrix:
point1    point2    distance
1              1            0
1              2            4
2              2            0
2              1            4
Please let me know if there is a
2012 Dec 13
1
Pairwise deletion in a linear regression and in a GLM ?
Dear useRs,
In a thesis, I found a mention of the use of pairwise deletion in linear
regression and GLM (binomial family).
The author said that he has used R to do the statistics, but I did not find
the option allowing pairwise deletion in both lm and glm functions. Is
there somewhere a package allowing that ?
Thanks,
Arnaud
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2011 Dec 18
0
fst, wine, Kontakt5 ... still no joy
Hi,
(Sorry for the cross-posting.)
After manually installing the 32-bit libjack packages on my 64-bit system,
the original problem ("Can't connect to JACK") is gone; now I get a 
whole new set of errors instead :)
When I try to start the Kontakt 5 VST from festige (via fst, via WINE), 
this is what I get:
============================
----------------yo... lets see...
2009 Jul 27
1
supporting --fake-super on opensolaris (zfs) destination
Hello everybody. I wrote a small patch in order to support what I think
is an absolutely needed feature in order to make rsync-based backups
retaining complete ownership permission when writing to an opensolaris
machine using --fake-super.
My goal is making backups of linux boxes to opensolaris/zfs.
In order to make it work just do 
patch -p1 < patch_file.txt
inside rsync source tree.
and
2011 Nov 01
1
help with unequal variances
Hello,
I have some patient data for my masters thesis with three groups (n=16, 19 &
20)
I have completed compiling the results of 7 tests, for which one of these
tests the variances are unequal.
I wish to perform an ANOVA between the three groups but for the one test
with unequal variance (<0.001 by both bartlett and levene's test) I am not
sure what to do.
I thought i would run
2017 Jun 17
1
dist function in R is very slow
Dear R developers,
I am visualising high dimensional genomic data and for this purpose I need to compute pairwise distances between many points in a high-dimensional space (say I have a matrix of 5,000 rows and 20,000 columns, so the result is a 5,000x5,000 matrix or it's upper diagonal).Computing such thing in R takes many hours (I am doing this on a Linux server with more than 100 GB of RAM,