similar to: Fisher's r to z' transformation - help needed

Displaying 20 results from an estimated 800 matches similar to: "Fisher's r to z' transformation - help needed"

2002 Jul 26
3
Fisher r-to-z transformation
Hi everyone, I want to use the Fisher r-to-z transformation as part of a hypothesis test of r. I can't find an R function that can do that. Am I missing it? -Tim -- Tim Wilson | Visit Sibley online: | Check out: Henry Sibley HS | http://www.isd197.org | http://www.zope.com W. St. Paul, MN | | http://slashdot.org wilson at visi.com | <dtml-var
2003 Aug 06
1
Standard error of standard deviation: bootstrap or theoretical results?
Dear R users, This is more a statistical question rather than an R question. I'd appreciate it if you can give me some suggestions. I have a sample of a time series (sample size 500, fat tail in density). I am trying to calculate the Standard error of standard deviation of a sub-block-sample (sample size 250). I take 100 this kind of sub-block-sample, randomly. For these 100 subsamples, I
2010 Nov 29
2
Significance of the difference between two correlation coefficients
Hi, based on the sample size I want to calculate whether to correlation coefficients are significantly different or not. I know that as a first step both coefficients have to be converted to z values using fisher's z transformation. I have done this already but I dont know how to further proceed from there. unlike for correlation coefficients I know that the difference for z values is
2007 May 30
1
test to compare significant correlation increase
Hi! I am calculating correlation between two variables: 1. X versus Y 2. X versus Y(with a 3 steps lag) I would like to test if the correlation increase/decrease from 1 to 2 is significant or not. Is there any function in R to do this? any hints? Thanks for help :) David Ria?o Center for Spatial Technologies and Remote Sensing (CSTARS) University of California 250-N, The Barn One Shields
2005 Sep 13
1
Fisher's exact test vs Chi-square
Timothy, I believe you are mistaken. Fisher's exact test give the correct answer even in the face of small expected values for the cell counts. Pearson's Chi-square approximates Fisher's exact test and can give the wrong answer when expected cell counts are low. Chi-square was developed because it is computationally "simple". Fisher's exact test, particularly with tables
2013 Feb 08
1
Contrasts for a data
Hi, I am using a data called Rail in the nlme package. The data contains two variables: Rail and Travel. >Rail Grouped Data: travel ~ 1 | Rail Rail travel 1 1 55 2 1 53 3 1 54 4 2 26 5 2 37 6 2 32 7 3 78 8 3 91 9 3 85 10 4 92 11 4 100 12 4 96 13 5 49 14 5 51 15 5 50 16 6 80
2007 Jun 16
0
Fwd: How to set degrees of freedom in cor.test?
You could calculate the confidence interval of the correlation at your desired df: http://davidmlane.com/hyperstat/B8544.html The below code takes as arguments the observed correlation, N, and alpha, calculates the confidence interval and checks whether this includes 0. cor.test2=function(r,n,a=.05){ phi=function(x){ log((1+x)/(1-x))/2 } inv.phi=function(x){
2010 May 12
1
fisher's posthock test or fisher's combination test
Hi to all is there a fisher's post hock test or fisher's combination test in R available? Maybe not -- its very easy to do it in excel ... Kind regards Knut
2006 Aug 05
1
Interpretation of call to aov()
Hi all, I've been reading about aov() at http://www.psych.upenn.edu/~baron/rpsych/rpsych.html and http://davidmlane.com/hyperstat/intro_ANOVA.html and I try to use this test in experiments with my simulator. What I would like Anova to tell me is whether the differences I see when plotting the means of performance per method are significant. And also, whether this is dependent on the problem
2003 Apr 22
4
fisher exact vs. simulated chi-square
Dear All, I have a problem understanding the difference between the outcome of a fisher exact test and a chi-square test (with simulated p.value). For some sample data (see below), fisher reports p=.02337. The normal chi-square test complains about "approximation may be incorrect", because there is a column with cells with very small values. I therefore tried the chi-square with
2005 Sep 29
1
Fisher's discriminant functions
Hi everyone, I'm trying to solve a problem about how to get the Fisher's discriminant functions of a "lda" (linear discriminant analysis) object, I mean, the object obtained from doing "lda(formula, data)" function of the package MASS in R-project. This object gives me the canonical linear functions (n-1 coefficients matrix of n groups at least), and only with this
2009 Jul 17
2
Fisher's exact test
Hi, I'm trying to run Fisher's Exact test on the data below, but I'm not sure how interpret the data shown. Can someone tell me what this is saying? Looking at the numbers it should be that there's no significant difference between the HDL and LDL, but a p-value of 1 seems high. Is the low value in the LDL unbound making the test unstable and should I be using an alternative? Best
2005 Sep 05
2
Fisher's method in discriminant analysis
Hi, I'm using mda library to solve a discriminant analysis. I get results, but the thing is that I want to use Fisher's method to obtain the classification functions and I'm lost in what I should do: libraries to use, ... Can anybody give me a clue?? Thanks. Carlos Niharra L??pez
2011 Apr 13
1
Previously attainable fisher's exact test
I have a matrix say, 1 4 23 30 and I want to find the previously attainable fisher's exact test p-value. Is there a way to do this in R? -- Thanks, Jim. [[alternative HTML version deleted]]
2005 Apr 20
1
negative p-values from fisher's test (PR#7801)
Full_Name: Martha Nason Version: 2.0.1 OS: Windows XP Submission from: (NULL) (137.187.154.154) I am running simulations using fisher's test on 2 x c tables and a very small p.value from fisher's test (<2.2e-16) is returned as a negative number. Code follows. > set.seed(0) > nreps.outer <-7 > pvalue.fisher <- rep(NA,nreps.outer) > > population1 <- c(
2006 Apr 04
0
Fisher's discriminant functions
Hi, I am trying to solve a discriminant analysis in the same way as SPSS does it. I mean, given an amount of data, to train the discriminant analysis I obtain the Fisher's discriminant functions, an array of coefficients per group, so if I have 8 groups I get 8 linear functions, that allow me to operate with them easily and without a great cost of time. My main problem is that I need to
2006 Jul 11
1
Table of P values for Fisher's exact test
Hi, I have a table of observed counts for various genetic markers. Instead of doing Fisher's exact test for each marker one at a time and recording the P value manually, is there a script to go through the whole list and generate the P value column automatically? An example of my data: Counts_CHB and Counts_AA are the observed counts for one allele. 2N_CHB and 2N_AA are the total number
2011 Jan 18
1
Choosing statistical test - Fisher's Exact Test?
Hi I was wondering whether anyone can help me with this problem....it's been driving me nuts, I've been trying to figure it out for months and months without success!! Basically I have a group of participants who attended 2 experimental sessions a few months apart. I took measures of the way they approach two tasks at Time 1 and the same two tasks at Time 2. I have categorical data (a
2012 Apr 03
1
Fisher's LSD multiple comparisons in a two-way ANOVA
Hi there, Is there a function that can do a Fisher's LSD multiple comparisons in a two-way ANOVA? I hope to get a result similar with TukeyHSD(). Especially, I hope to know the significance of comparisons between the interactions of two factors. In the following example: x <- c(76, 84, 78, 80, 82, 70, 62, 72, 71, 69, 72, 74, 66, 74, 68, 66, 69, 72, 72, 78, 74, 71, 73, 67, 86, 67, 72,
2010 Mar 06
0
Fisher's LSD and tukey output thing
Hi there, ============================= x=c(145,40,40,120,180, 140,155,90,160,95, 195,150,205,110,160, 45,40,195,65,145, 195,230,115,235,225, 120,55,50,80,45 ) y2=c( rep(as.character(1),5), rep(as.character(2),5), rep(as.character(3),5), rep(as.character(4),5), rep(as.character(5),5), rep(as.character(6),5) ) crd2=data.frame(x,y2) model1=aov(x~y2,data=crd2) TukeyHSD(model1)