Displaying 20 results from an estimated 1000 matches similar to: "Wilcox Test / Mann Whitney U Test"
2007 Jul 31
5
Dropouts and echo
Hi all,
We have recently implemented an Asterisk system using Trixbox
(asterisk v1.4.4 at the moment, yet to move to 1.4.9) but are getting
pressure to switch back to our old key system unless we fix two major
issues. So please help me avoid switching back!
An overview: We have about 12 Linksys SPA941 SIP phones connected on
a private switched network to our asterisk box which is a
2004 Mar 10
1
Rank Simulations - Test statistic Help
Hi all,
I am a biostatistician and I have developed my own
ranking system for clinical data. I would like to test
the efficiency of it w.r.t. to other ranking systems.
I would like to simulate the data and after assigning
ranks to my observed scores(after neglecting
dropouts), observe the type I error. If I want to do a
Kruuskal Wallis type of test, what test statistic
should I use to test for a
2012 Feb 12
3
Sound drop out with totem. mplayer Can't open audio device /dev/dsp
Hey all.
This morning I found that my audio playback is randomly sprinkled with
sound skips and dropouts. I went to /var/log/yum.log and found this:
Feb 09 20:18:22 Updated: lame-3.99.4-2.el6.rf.i686
I'm not saying that caused the problem but it's all I could find that
changed.
When I ls in /dev there is no dsp entry.
That would explain why mplayer Can't open audio device
2004 May 07
7
Asterisk and Cisco 7960 problems persist (for me, anyway)
It seems that each time I get a new checkout of * from CVS my Cisco 7960
works worse than before. I know this stuff's in flux, so I mention this
in case it's news. Anyone else having trouble? What I'm seeing (er,
hearing) is really choppy audio. The previous version I had installed
had fairly frequent audio dropouts (not present when I make the same
calls through the same * box
2004 Sep 21
2
RC1 still broken with Cisco 7960?
After downloading the latest CVS head and testing it with the Cisco 7960
(SIP v7.2), it appears that it's still necessary to patch rtp.c to avoid
audio dropouts.
I'm quite sure my gateway provider is running an older version of
Asterisk, and I suppose that this may be the root cause. But I mention
the issue here because it seems like it would be a mistake to ship
Asterisk 1.0 if it
2004 Dec 17
2
OT: "Integrated Access T1" voice problems - is this possible?
Hello,
I am currently pricing out various T1 and PRI options for a client of
mine. We need voice and data - we want T's. Whether it be two seperate
T's, two superate fractional T's, or one combined fractional T, we need
it done.
We are getting pricing and one provider is telling us that they have
quality issues with the "Integrated Access" product. From what they
2012 Jul 06
1
Mann-Whitney by group
Hello,
I'm having some issues grouping cases for some Mann-Whitney U tests I'm attempting to run. I'm willing to use wilcox.test if it'll work; I've also tried wilcox_test() from the "coin" package. Here's the deal: for each column (A through H), I would like to run the two-sample independent test, comparing Group 5 (CD8.14 through CD8.17) to Group 6 (CD8.18
2005 Feb 24
0
How to code a bootstrap version of the Wilcoxon-Mann-Whitney test?
Dear Stefan
I need to apply a Mann Whitney test to my data, by applying a bootstrap, in
R.
Loonkig for an answer in internet I found your question to the R mailing
list but I have not found the answer to your question.
Please, could you help me?
thank you very much in advance.
Best regards
Luciana
2003 Aug 26
1
Mann-Whitney U Table
Does anyone have a piece of code or know how I can use R to generate a table
of
critical values for the Mann-Whitney (aka Wilcoxon Rank Sum) test.
Ideally, I'd like a table that contains the critical values for any two
samples of size 3 through 30. I could use Monte Carlo simulation or the
normal approximation when n1 and n2 are greater than, 10, but I figured
someone may know how to
2005 Dec 20
1
Wilcoxon Mann-Whitney Rank Sum Test in R
An earlier post had posed the question: "Does anybody know what is relation
between 'T' value calculated by 'wilcox_test' function (coin package) and
more common 'W' value?"
I found the question interesting and ran the commands in R and SPSS. The W
reported by R did not seem to correspond to either Mann-Whitney U,
Wilcoxon W or the Z which I have more
2007 Aug 15
0
Mann-Whitney U test discrepancies
Hi,
I do want to use the Mann-Whitney test which ranks my data and then
uses
those ranks rather than the actual data.
Here is the R code i am using:
group1<-
c(1.34,1.47,1.48,1.49,1.62,1.67,1.7,1.7,1.7,1.73,1.81,1.84,1.9,1.96,2,
2,2.19,2.29,2.29,2.41,2.41,2.46,2.5,2.6,2.8,2.8,3.07,3.3)
> group2<-
2009 Feb 14
1
Mann Whitney test
Hi,
I have a statistical question.
To apply the Mann Whitney test to compare a pair of vectors, they must to
have the same length ?
Thanks,
Rodrigo
[[alternative HTML version deleted]]
2009 Jul 11
2
mann-whitney U-test - U-value
Hi,
I know that I can perform a Mann-Whitney U test with wilcox.test(x,y)
But instead of an U-value I get a W-Value.
Is it possible to change this?
2009 Sep 07
1
Equivalence of Mann-Whitney test and Kruskal-Wallis test with k=2
Hi all,
The Kruskal-Wallis test is a generalization of the two-sample Mann-Whitney
test to *k* samples. That being the case, the Kruskal-Wallis test with *k*=2
should give an identical p-value to the Mann-Whitney test, should it not?
x1<-c(1:5)
x2<-c(6,8,9,11)
a<-wilcox.test(x1,x2,paired=FALSE)
b<-kruskal.test(list(x1,x2),paired=FALSE)
a$p.value
[1] 0.01587302
b$p.value
[1]
2009 Nov 18
1
mann-whitney test with more groups
Dear r-helpers,
I want to test groups of samples for significant differences.
Question: Does Group1 differ significantly from group2.
This is a question to be answered by mann-whitney-u-test.
I know that I can use wilcox.test with 2 samples.
My problem: How can r perform the test automatically if there are more than 2 groups in my data frame.
Test group1 vs. 2, 1 vs. 3, 1 vs. 4, etc.
This is
2010 Oct 26
1
Time series data with dropouts/gaps
I have time-series data from a pair of inexpensive self-logging 3-axis accelerometers (http://www.gcdataconcepts.com/xlr8r-1.html). Since I'm not sure of the vibration/shock spectrum I'm measuring, for my initial sensor characterization run the units were mounted together with the sample rate set to the maximum of 640 samples/sec.
Unfortunately, at this sample rate there are significant
2005 May 16
1
Mann-Whitney & Wilcoxon Rank Sum
Hello,
I am hoping someone could shed some light into the Wilcoxon Rank Sum Test
for me? In looking through Stats references, the Mann-Whitney U-test and
the Wilcoxon Rank Sum Test are statistically equivalent. When using the
following dataset:
m <- c(2.0863,2.1340,2.1008,1.9565,2.0413,NA,NA)
f <- c(1.8938,1.9709,1.8613,2.0836,1.9485,2.0630,1.9143)
and the wilcox.test command as
2004 Apr 19
1
SIP dropouts
Howdy all...
When making SIP calls through my X100P from X-Lite to the PSTN I'm
getting 3-5 second dropouts in both directions. I've tried ulaw and
GSM, but that doesn't seem to make a difference, and the * box is on my
local net.
Here's my hardware: Celeron 2.4GHz, 512MB, Slackware 9.1, 2 X100P, 1 T100P.
Any ideas what could be happening, or pointers as to how to shoot this
2003 Feb 15
2
How to code a bootstrap version of the Wilcoxon-Mann-Whitney test (and variants)?
Hello,
can someone please help me with coding a function for a bootstrap WMW test (package boot, R under Windows, version 1.6.2)?
2009 Aug 26
3
mann whitney u
Dear Sir,
I am comparing two samples using wilcox.test in R. Literature appears to describe mann whitney u test as the most appropriate test to use on my data.
is the wilcox.test function equivalent to mann-whitney u? Is there a way to gain the U-value as apposed to the W-value in R?
Thank you