Displaying 20 results from an estimated 4000 matches similar to: "have to point it out again: a distribution question"
2005 Apr 22
1
an interesting qqnorm question
Hi, r-gurus:
I happened to have a question in my work:
I have a dataset, which has only one dimention, like
0.99037297527605
0.991179836732708
0.995635340631367
0.997186769599305
0.991632565640424
0.984047197106486
0.99225943762649
1.00555642128421
0.993725402926564
....
the data is saved in a file called f392.txt.
I used the following codes to play around :)
2011 Dec 21
4
qqnorm & huge datasets
Hi,
When qqnorm on a vector of length 10M+ I get a huge pdf file which
cannot be loaded by acroread or evince.
Any suggestions? (apart from sampling the data).
Thanks.
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2011 Apr 30
4
QQ plot for normality testing
Hi all,
I am trying to test wheater the distribution of my samples is normal with QQ plot.
I have a values of water content in clays in around few hundred samples. Is the code :
qqnorm(w) #w being water content
qqline(w)
sufficient?
How do I know when I get the plots which distribution is normal and which is not?
Thanks, m
[[alternative HTML version
2003 Aug 15
6
plot.lm mislabels points with na.exclude (PR#3750)
R 1.7.1 on Windows XP
The "normal Q-Q plot" produced by plot.lm() mislabels points
when the model is fitted using na.action=na.exclude. Example:
x <- 1:50
y <- x + rnorm(50)
y[c(5,10,15)] <- NA # insert some NA's
y[40] <- 50 # add an outlier
plot(lm(y ~ x, na.action=na.omit)) # outlier correctly labeled in all
# four plots
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.
2017 Jul 06
3
Efficient swapping
Thanks a lot, Ista! I really appreciate it.
How about a slightly different case as the following:
set.seed(1)
(tmp <- data.frame(x = 1:10, R1 = sample(LETTERS[1:5], 10, replace =
TRUE), R2 = sample(LETTERS[2:6], 10, replace = TRUE)))
x R1 R2
1 C B
2 B B
3 C E
4 E C
5 E B
6 D E
7 E E
8 D F
9 C D
10 A E
Notice that the factor levels between
2017 Jul 06
2
Efficient swapping
Suppose that we have the following dataframe:
set.seed(1)
(tmp <- data.frame(x = 1:10, R1 = sample(LETTERS[1:5], 10, replace =
TRUE), R2 = sample(LETTERS[1:5], 10, replace = TRUE)))
x R1 R2
1 1 B B
2 2 B A
3 3 C D
4 4 E B
5 5 B D
6 6 E C
7 7 E D
8 8 D E
9 9 D B
10 10 A D
I want to do the following: if the difference between the level index
of factor
2000 Feb 24
2
(-1 as index) OR (envelope for QQ)
I'm new to R (and to S) and am wondering about code from pages 72 and
83 of MASS (Venables+Ripley, 3rd edition), to draw an envelope on a QQ
plot. Copying from the book, I've got:
#... code whose gist is "a.fit <- nls(..."
num.points <- length(resid(a.fit))
qqnorm(residuals(a.fit)) # illustrate data-model residuals
qqline(residuals(a.fit))
samp <-
2007 Dec 06
1
correlation coefficient from qq plot
Hi,
I am trying to figure out how to get the correlation coefficient for a
QQ plot (residual plot). So to be more precise, I am creating the plot
like this:
qq.plot(rstudent(regrname), main = rformula, col=1)
But want to also access (or compute) the correlation coefficient for
that plot.
Thanks,
Tom
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2017 Jul 06
0
Efficient swapping
How about
foo <- with(list(r1 = tmp$R1,
r2 = tmp$R2,
swapme = (as.numeric(tmp$R1) - as.numeric(tmp$R2)) %% 2 != 0),
{
tmp[swapme, "R1"] <- r2[swapme]
tmp[swapme, "R2"] <- r1[swapme]
tmp
})
Best,
Ista
On Thu, Jul 6, 2017 at 4:06 PM, Gang Chen <gangchen6 at gmail.com> wrote:
> Suppose that we have the following
2017 Jul 06
0
Efficient swapping
Untested, but I expect that setting the levels to be the same across the
two factors
levels(tmp$R1) <- levels(tmp$R2) <- LETTERS[1:6]
and proceeding as before should be fine.
Best,
Ista
On Jul 6, 2017 6:54 PM, "Gang Chen" <gangchen6 at gmail.com> wrote:
Thanks a lot, Ista! I really appreciate it.
How about a slightly different case as the following:
set.seed(1)
(tmp
2005 Jul 07
2
randomForest
> From: Weiwei Shi
>
> it works.
> thanks,
>
> but: (just curious)
> why i tried previously and i got
>
> > is.vector(sample.size)
> [1] TRUE
Because a list is also a vector:
> a <- c(list(1), list(2))
> a
[[1]]
[1] 1
[[2]]
[1] 2
> is.vector(a)
[1] TRUE
> is.numeric(a)
[1] FALSE
Actually, the way I initialize a list of known length is by
2009 Sep 17
2
QQ plotting of various distributions...
Hello!
I am trying with this question again:
I would like to test few distributional assumptions for some behavioral
response data. There are few theories about true distribution of those
data, like: normal, lognormal, gamma, ex-Gaussian
(exponential-Gaussian), Wald (inverse Gaussian) etc. The best way would
be via qq-plot, to show to students differences. First two are trivial:
qqnorm(dat$X)
2016 Apr 04
2
question about probplot in e1071 package
Hello!
I am using probplot in the e1071 package and want to do something like the
following, only with the the 2nd plot overlaying the first. I can't seem to
make it work. Any suggestions?
*library(e1071)
**x <- rnorm(100, mean=5)*
*y <- rnorm(100, mean=3)*
*probplot(x, line=FALSE)
*
*probplot(y, line=FALSE)
*
*Regards,*
*Tom*
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2005 Jul 02
1
probability-probability plot
Hi, there.
Is there any function in R to plot the probability-probability plot (PP
plot)? Suppose I am testing some data against normal.
Thanks.
Yulei
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yuleih at umich.edu
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2009 Nov 06
4
PRUEBAS DE NORMALIDAD
Estimados todos:
Me es grato escribir a esta lista de ayuda para R, ya que comparto 100% la filosofĂa de Software libre en especial software en EstadĂstica ya que es la carrera que estoy siguiendo.
El motivo de este mensaje es por un par de dudas que no pude resolver:
1. He utilizado las funciones para realizar pruebas de normalidad (kolmogorov-smirnov, cuando n>50) y (Shapiro, cuando
2009 Dec 28
1
Help With Custom QQ Plot
Good Morning:
I have attached a text file with one hundred thirty six observations. I would like to create a qq plot with the following features:
1. Observed values on the y-axis.
2. Normal approximation line on the plot.
3. X-axis with vertical reference lines at the following percentiles of the data: 1, 10, 20, 50, 80, 90 and 99.
4. Data appearing on the plot as distinct points.
I assume that
2012 Feb 10
1
Formatting Y axis.
I've looked around and I just can't find anything that will work for my
needs. This is a bit of a 2 part question but pertaining to the same topic
so bare with me.
The first is with my qq plot. On the Y axis of my qq plot it'll have my
sample quantities but because my data is log-normal it'll show numbers
between 0 - 5 (depending on the data). I'd like to know how to get it,
2013 May 27
1
Plot histograms in a loop
Hi,
Try either:
set.seed(28)
stats1<- as.data.frame(matrix(rnorm(5*10000),ncol=5))
pdf(paste("test",1,".pdf",sep=""))
par(mfrow=c(2,1))
lst1<- lapply(names(stats1),function(i) {hist(stats1[,i],100,col="lightblue",main=paste0("Histogram of ",i),xlab=i );qqnorm(stats1[,i])})
dev.off()
#or
2005 Jul 18
1
read large amount of data
Hi,
I have a dataset with 2194651x135, in which all the numbers are 0,1,2,
and is bar-delimited.
I used the following approach which can handle 100,000 lines:
t<-scan('fv', sep='|', nlines=100000)
t1<-matrix(t, nrow=135, ncol=100000)
t2<-t(t1)
t3<-as.data.frame(t2)
I changed my plan into using stratified sampling with replacement (col
2 is my class variable: 1 or 2).