Displaying 20 results from an estimated 400 matches similar to: ""normal probability plot" with a percentile scale?"
2007 Jul 04
2
probabilty plot
Hi all,
I am a freshman of R,but I am interested in it! Those days,I am
learning pages on NIST,with url
http://www.itl.nist.gov/div898/handbook/eda/section3/probplot.htm,
I am meeting a problem about probability plot and I don't know how to
plot a data set with R.
Could somebody tell me the answer,and a example is the best! I will
look forward to your answer.
Thank you very much.
2012 Feb 02
9
Modelo senoidal de datos temporales de radiación y prueba de Thom
Hola a todos:
Estoy intentado realizar un modelo senoidal de unos datos de radiación
solar con el fin de afrontar el relleno de la serie y aplicar la prueba
de Thom para verificar su homogeneidad [0].
De momento me encuentro con los siguientes problemas:
1- ¿Existe la prueba de Thom en R? ¿O debo crearme mi propia función?
2- Para la realización del modelo senoidal estoy siguiendo los pasos
2005 Jan 13
2
chisq.test() as a goodness of fit test
Dear R-Users,
How can I use chisq.test() as a goodness of fit test?
Reading man-page I?ve some doubts that kind of test is
available with this statement. Am I wrong?
X2=sum((O-E)^2)/E)
O=empirical frequencies
E=expected freq. calculated with the model (such as
normal distribution)
See:
http://www.itl.nist.gov/div898/handbook/eda/section3/eda35f.htm
for X2 used as a goodness of fit test.
Any
2006 Mar 13
1
bihistogram plots
Does anyone have code to plot bihistograms in R?
See http://www.itl.nist.gov/div898/handbook/eda/section3/bihistog.htm
for a description of
a bihistogram.
--
Hal Varian voice: 510-643-4757
SIMS, 102 South Hall fax: 510-642-5814
University of California hal at sims.berkeley.edu
Berkeley, CA 94720-4600 http://www.sims.berkeley.edu/~hal
2005 Jan 11
3
Kolmogorov-Smirnof test for lognormal distribution with estimated parameters
Hello all,
Would somebody be kind enough to show me how to do a KS test in R for a
lognormal distribution with ESTIMATED parameters. The R function
ks.test()says "the parameters specified must be prespecified and not
estimated from the data" Is there a way to correct this when one uses
estimated data?
Regards,
Kwabena.
--------------------------------------------
Kwabena Adusei-Poku
2009 Dec 22
2
ACF normalization.
Hi,
Can anyone please provide the formula used to compute ACF(nlme). I believe the one that is used in R is of the type mentioned on the website. Please correct me if I am wrong. The normalization of the numerator (Ch) has been done by 'N' where as I would like to do it by 'N-k'. Is there anyway in the present implementation of ACF to normalize it by 'N-k', where
2004 Nov 17
1
R: log-normal distribution and shapiro test
Hi,
from what you're writing:
"The logaritmic transformation
"shapiro.test(log10(y))" says: W=0.9773, p-value=
2.512e-05." it seems the log-values are not
distributed normally and so original data are not
distributed like a log-normal: the p-value is
extremally small!
Other tests for normality are available in package:
nortest
compare the log-transformation of your ecdf
2007 Jul 27
1
R codes for g-and-h distribution
hi!
I would like to ask help how to generate numbers from g-and-h distribution. This distribution is like normal distribution but span more of the kurtosis and skewness plane. Has R any package on how to generate them?
Any help will be greatly appreciated. Thank you so much!
Form,
Filame Uyaco
---------------------------------
[[alternative HTML version deleted]]
2005 Jan 21
0
R: chi-Squared distribution in Friedman test
Hi,
pchisq -> distribution function
dchisq -> density function
pval is the area under the curve, to calculte it you
use distribution function which is the integral of
density function. See:
http://www.itl.nist.gov/div898/handbook/eda/section3/eda362.htm
http://mathworld.wolfram.com/DistributionFunction.html
f(x) density function
F(x) distribution function =Pr(X<x)= integral(f(x))
2008 Oct 23
3
Interpretation of t.test results
I have run a t.test in R, and received these results:
Two Sample t-test
data: rsa and umple
t = 0.9819, df = 10, p-value = 0.3493
alternative hypothesis: true difference in means is not equal to 0
95 percent confidence interval:
-76.1541 196.1541
sample estimates:
mean of x mean of y
508.3333 448.3333
Can someone give me a detailed interpretation of the above results?
Specifically,
2007 Apr 12
3
Putting 2 breaks on Y axis
R plotting experts:
I have a bivariate dataset composed of 300 (x,y) continuous datapoints.
297 of these points are located within the y range of [0,10], while 2
are located at 20 and one at 55. No coding errors, real outliers.
When plotting these data with a scatterplot, I obviously have a problem.
If I plot the full dataset with ylim = c(0,55), then I cannot see the
structure in the data in
2004 Apr 06
2
percentile-percentile plot
Hi,
Is there a function that does percentile-percentile plot. I do not mean
the qqplot. I need to plot the percentiles rather than points themselves.
I am hoping for a plot that tells me that the x percentile of one data set
corresponds to the y percentile of the other. for example a point on the
plot of (.5, .2) will tell me that the 50th percentile of the first data
and the 20th percentile of
2008 Jun 28
0
How to get the 5th percentile( with a 95% CI )of the Kaplan-meier estimator?
Hi, all dear R experts,
I am really stuck by how to get the 5th percentile( with a 95% CI )of the Kaplan-meier estimator of survival function P(T>t). I have a simulated sample of lifetime Ts, then I set the KM estimator
< km.fit<-survfit(Surv(T),type="kaplan-meier",data=Surv(T))
<quantile(km.fit,.05)
However, it gave "Error in order...". Does someone have some
2002 Aug 09
0
percentile labels in qqnorm
Hi-
I wanted percentage labels on a qqnorm x axis. I used the following:
#make up some data
jt<-rnorm(100)
#qqnorm with percentile x labels
qqnorm(jt,axes=F,xlab="Percentiles")
box()
l<-c(1,5,10,30,50,70,90,95,99)
axis(1,at=qnorm(l/100),label=l)
which was ok for this data set.
Does anyone have a more general solution which would allow one to
specify the number of x labels
2006 Jul 24
2
How to obtain 95th percentile of a normal distribution of a continuous variable
Hi,
How do I get R to output the 95% cutoff from a distribution of a continous
variable?
summary() only displays a few statistics....
Thanks!
2008 May 16
1
(1-alpha)th percentile
hello;
firstly, my gratitude to all who help me to find a function that allows me
to add confidence interval to my graph.
in order to calculate the (1-alpha)th percentile of for exemple an
F(df1,df2) distribution i do like this:
v<-df(alpha,df1,df2)
percentile<-qf(v,df1,df2,alpha)
if it is true please alert me , and if it is not what should do then?
:handshake:
--
View this message in
2008 Jul 25
1
Percentile Estimation From Kernel Density Estimate
Has anyone developed a defensible method of estimating percentiles from a
univariate kernel density estimate? I am working on a problem in which the
density estimate is of interest, but I would also like to estimate the
value of the variable for which the distribution was, say, 0.20. I spent
some time searching the archives and found some message from 2006 that
implied such a method was not
2010 May 28
1
create new variable: percentile value of variable in data frame
Hello all,
Thanks in advance for you attention.
I would like to generate a third value that represents the quantile
value of a variable in a data frame.
# generating data
x <- as.matrix(seq(1:30))
y <- as.matrix(rnorm(30, 20, 7))
tmp1 <- cbind(x,y)
dat <- as.data.frame(tmp1)
colnames(dat) <- c("id", "score")
dat
# finding percentiles of "score"
2010 Sep 07
2
Percentile rank for each element in list
Heeeelp
Given this data
x <- c(1,5,100,300,250,200,550,900,1000)
> quantile(x)
0% 25% 50% 75% 100%
1 100 250 550 1000
When I run the quantile, I can only know the value of the nth
percentile
I want to know what's the percentile position of each items in the
list
Sample
1 = 100% on the list has 1 or more
5 = more than x% on the list has 5 or more
100 = more than x% on the
2012 Sep 28
1
z-score to percentile, and back again (Normal)
In R, what is the best way to convert z-scores (Normal distribution) to a percentiles, and vice-versa.
(I'll be looking to do the same with other distributions eventually.)
===
Peter Petto <ppetto at ppetto.com>
Bay Village, OH 440.249.4289