similar to: Generating Hotelling's T squared statistic with hclust

Displaying 20 results from an estimated 4000 matches similar to: "Generating Hotelling's T squared statistic with hclust"

2007 Feb 20
1
Mahalanobis distance and probability of group membership using Hotelling's T2 distribution
I want to calculate the probability that a group will include a particular point using the squared Mahalanobis distance to the centroid. I understand that the squared Mahalanobis distance is distributed as chi-squared but that for a small number of random samples from a multivariate normal population the Hotellings T2 (T squared) distribution should be used. I cannot find a function for
2007 Apr 15
4
Hotelling T-Squared vs Two-Factor Anova
Hi, I am a graduate student at Stanford University and I have a general statistics question. What exactly is the difference between doing a two-factor repeated measures ANOVA and a Hotelling T-squared test for a paired comparison of mean vectors? Given: Anova: repeated measures on both factors, 1st factor = two different treatments, 2nd factor = 4 time points, where you are measuring the blood
2011 Dec 01
2
How to do Hotelling's t2 test?
Hi, I want to do a 2 sample hotelling's test but i can't figure out how. When i type T2.test it says there is no such test and when i tried library(rrcov) it says there is no such program. Cheers. -- View this message in context: http://r.789695.n4.nabble.com/How-to-do-Hotelling-s-t2-test-tp4128748p4128748.html Sent from the R help mailing list archive at Nabble.com.
2005 Jun 21
1
test for equality of two data sets with multidimensional variables
Hello there, I have two data sets with 14 variables each, and wish to do the test for equality of their covariance matrices and mean vectors. Normally these tests should be done by chi square test (box provided) and Hotelling's T square test respectively. Which R functions could do this kind of test? I just find some functions could do for one dimension, but no for multidimension. Some one
2010 Jun 13
1
Finding an order for an hclust (dendrogram) object without intersections
Hello all, I manually created an hclust object. Now I am looking to reorder the leafs so they won't intersect with each other, and would be happy for advises on how to do that. Here is an example code: #------------------------------------- a <- list() # initialize empty object # define merging pattern: # negative numbers are leaves, # positive are merged clusters (defined by row
1998 Nov 11
1
MANOVA / Hotelling's Test
Hi everybody ... I have to perform Hotteling's T^2 Test - more generally a MANOVA - on a set of data. Is there a (simple?) possibility to do it in R? The somewhat obvious way to do it would be > summary(aov(Y ~ x1 + x2 ... + xn)) where Y would be a two-column matrix. But this does not work in any possible combination of matrix or factor dimensions! Is it principally not possible
2002 Feb 20
1
plot.hclust: strange behaviour with "manufactured" hclust object
I've been trying to get plot.hclust to work with a hclust object I created and have not had much success. It seems that there is some "hidden" characteristic of a hclust object that I can't see. This is most easily seen in the following example, where plot.hclust works on one object, but when this object is "dumped" and then re-read, plot.hclust no longer works. Is
2013 Dec 12
2
method default for hclust function
I could not figure out what was the default when I ran hclust() without specifying the method. For example: I just have a code like: hclust(dist(data)) Any input would be appreciated:) [[alternative HTML version deleted]]
2010 Dec 27
1
Any functions to manipulate (merge, cut, remove) hclust objects? (maybe through phylo?)
Hello all, I'm now working with hclust objects and was hoping to perform some basic editing on them like: - Joining = the merging of two hclust objects (so they will share one root) - Splicing = So to cut/extract a branch out of an hclust object - that by itself will be an hclust object. I noticed I could extract one element of an hclust object by turning it into a dendrogram,
2011 Sep 13
2
help with hclust and cutree
Hello, I would like to cut a hclust tree into several groups at a specific similarity. I assume this can be achieved by specifying the "h" argument with the specified similarity, e.g.: clust<-hclust(dist,"average") cut<-cutree(clust,h=0.65) Now, I would like to draw rectangles around the branches of the dendrogram highlighting the corresponding clusters, as is done by
2002 May 30
1
hclust.identify problem
Having some problems with using hclust.identify on my data, I revert to trying it out on the example in the help manual. My result is still the same (as with my own data): data(iris) hci <- hclust(dist(iris[,1:4])) plot(hci) testx<-identify.hclust(hci) Error in rect.hclust(x, k = k, x = x$x, cluster = cluster[, k - 1], border = "red") : k must be between 2 and 0
2010 Nov 15
2
hclust, does order of data matter?
Hello, I am using the hclust function to cluster some data. I have two separate files with the same data. The only difference is the order of the data in the file. For some reason, when I run the two files through the hclust function, I get two completely different results. Does anyone know why this is happening? Does the order of the data matter? Thanks, RC -- View this message in
2012 Oct 11
2
extracting groups from hclust() for a very large matrix
Hello, I'm having trouble figuring out how to see resulting groups (clusters) from my hclust() output. I have a very large matrix of 4371 plots and 29 species, so simply looking at the graph is impossible. There must be a way to 'print' the results to a table that shows which plots were in what group, correct? I've attached the matrix I'm working with (the whole thing
2011 Sep 13
2
help with hclust
Hello, how can I get the similarity value (i.e., the inner cluster similarity) that was used to cut a hierarchical tree at a specific height? I would appreciate your help! Best regards, Madeleine
2004 Dec 15
1
hclust and heatmap - slightly different dendrograms?
Good afternoon, I ran heatmap and hclust on the same matrix x (strictly, I ran heatmap(x), and hclust(dist(t(x))), and realized that the two dendrograms were slightly different, in that the left-right arrangement of one pair of subclusters (columns) was reversed in the two functions (but all individual columns were grouped correctly). Looking through the code for heatmap as a most definite
2005 May 28
1
Forcing ticks in plot for hclust object outside the limits
Hello! I have the following problem. I would like to plot the hclust object "hcd" (bellow, at the end of the mail) with ticks at seq(0.05,0.25,by=0.05). I tried using the code plot(hcd) and plot(hcd,axes=FALSE) axis(2,seq(0.05,0.25,by=0.05)) In both cases, the resoult is the same, ticks at 0.05 and 0.25 are not printed. I tried changing the ylim argumet in plot, however I got a
2012 Jul 04
1
Error in hclust?
Dear R users, I have noted a difference in the merge distances given by hclust using centroid method. For the following data: x<-c(1009.9,1012.5,1011.1,1011.8,1009.3,1010.6) and using Euclidean distance, hclust using centroid method gives the following results: > x.dist<-dist(x) > x.aah<-hclust(x.dist,method="centroid") > x.aah$merge [,1] [,2] [1,] -3 -6
2003 Jul 13
1
bootstrap for hclust
dear group members, I am looking for a function that assess the stability of cluster. The result of hclust function is an hclust object which can be plot as a dendrogram. However to have confidence in the tree topology usualy bootstap is applied. I understand that I can apply bootstarp on the original data and then run hclust(dist() ) as much as I resampled but how to comapre the topologies the I
2012 Mar 29
2
hclust and plot functions work, cutree does not
Hi, I have the distance matrix computed and I feed it to hclust function. The plot function produces a dense dendrogram as well. But, the cutree function applied does not produce the desired list. Here is the code x=data.frame(similarity_matrix) colnames(x) = c(source_tags_vec) rownames(x) = c(source_tags_vec) clust_tree=hclust(as.dist(x),method="complete") plot(clust_tree)
2011 Feb 07
1
Creating a list of lists / hclust elements
Dear group, I am currently struggling with the following problem for a while: I want to create a list whose elements consists of lists themselves. More concise: The list elements are HCLUST objects. However, when I try to append the HCLUST objects to my list via: cluster_list <- append(cluster_list, HCLUSTobject) the HCLUST object is appended - but not as an object but as its components. So