Displaying 20 results from an estimated 6000 matches similar to: "Problem in performing goodness of fit test in R."
2010 Mar 13
2
Two questions, first about contingency tables, and second about table () and data.frame (), from a visually impaired user.
Hi all,
I want to make a contingency table in R. I want to tabulate two variables, one as the independent and second as the dependent variable. The IV has two categories, namely, birth complications, and no birth complications. The frequency of birth complication category is fifty, and the frequency of no birth complication category is 34. The categories and frequencies of DV follows.
2018 Feb 23
2
How to Save the residuals of an LM object greater or less than a certin value to an R object?
Dear list members,
I want to save residuals above or less than a certain value to an R
object. I have performed a multiple linear regression, and now I want
to find out which cases have a residual of above + 2.5 and ? 2.5.
Below I provide the R commands I have used.
Reg<-lm(a~b+c+d+e+f) # perform multiple regression with a as the
dependent variable.
Residuals<-residuals(reg) # store
2018 Mar 06
5
couple of how-to-do it in R questions regarding corelations and mean and SD of likert items
Dear list, I have the following how-to-do it in R, questions.
Suppose I have ten independent variables, and one dependent variable.
I want to find the Pearson correlation of all the IVs with the DV, but
not the correlation between the IVs.
What I know so far, about R, that I have to type the cor () function
ten times, each time requesting for a correlation between one IV and
the DV.
I was
2018 Feb 26
1
questions about performing Robust multiple regression using bootstrap
Dear list,
I am slightly confused about how I can do the following in R.
I want to perform robust multiple regression. I?ve used the Boot
function in CAR package to find confidence intervals and standard
errors. Inadition to these, I want to find the robust estimates for
the F test and r-square. Finally, I would like to know the
significance levels of bootstrap results.
Below I explain
2010 May 20
2
Reading results of commands in Microsoft Word typed in the terminal window, A question from a Blind R user.
Hi all,
I would like to read the results of the commands type in the terminal window in Microsoft Word. As a blind user my options are somewhat limited and are time consuming if I want to see the results of the commands that I have type earlier. for example if my first two commands were
x<-c(1,2,3,4,5)
mean(x)
and I have typed ten more commands after the first two commands it is not easy
2018 Feb 23
0
How to Save the residuals of an LM object greater or less than a certin value to an R object?
Residuals are stored as a numeric vector. The R software comes with a document "Introduction to R" that discusses basic math functions and logical operators that can create logical vectors:
abs( stdresiduals ) > 2.5
It also discusses indexing using logical vectors:
stdresiduals[ abs( stdresiduals ) > 2.5 ]
Note that in most cases it is worth going the extra step of making your
2018 Mar 06
0
couple of how-to-do it in R questions regarding corelations and mean and SD of likert items
Hi
For first question, maybe I am completely wrong but
cor(swiss[,-1], swiss[,1])
should give you what you want in one step.
Second question
Without an example it is hard to say but maybe aggregate is the way forward.
> aggregate(iris[,1:4], list(iris$Species), function (x) c(mean=mean(x), sd=sd(x)))
Group.1 Sepal.Length.mean Sepal.Length.sd Sepal.Width.mean Sepal.Width.sd
1
2010 May 21
2
Getting sink to work with “message” on R 2.11.0 - what did I miss?
Hi all,
I am trying to use type message with sink, like this:
sink("all.Rout", type="message")
1+3
sink()
readLines(con = "all.Rout")
So to get the following output:
> 1+3
[1] 4
Obviously this doesn't work.
I tried some variations (based on the explanations in the help) but am
missing something on how to make it work.
Any suggestions?
(p.s: I need
2010 May 22
2
Capturing R console output into a file (sink+savehistory ??)
After reading more, I understand I didn't formulate my last question
correctly, so please allow me to rephrase:
What I am looking for is a way to save the R console session output.
That is, a command that would combine the results of using:
?sink # And
?savehistory
My motivation for this is that doing it will allow someone who is a blind
user of R to be able to easily export his results to
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
2018 Feb 26
0
questions about performing Robust multiple regression using bootstrap
Dear Faiz,
Bootstrapping R^2 using Boot() is straightforward: Simply write a function that returns R^2, possibly in a vector with the regression coefficients, and use it as the f argument to Boot(). That will get you, e.g., bootstrapped confidence intervals for R^2. (Why you want that is another question.) See the example in ?Boot that shows how to bootstrap the estimated error variance (without
2014 May 07
3
historical significance of Pr(>Chisq) < 2.2e-16
Where does the value 2.2e-16 come from in p-values for chisq tests such
as those
reported below?
> Anova(cm.mod2)
Analysis of Deviance Table (Type II tests)
Response: Freq
LR Chisq Df Pr(>Chisq)
B 11026.2 1 < 2.2e-16 ***
W 7037.5 1 < 2.2e-16 ***
Age 886.6 8 < 2.2e-16 ***
B:W 3025.2 1 < 2.2e-16 ***
B:Age 1130.4 8 < 2.2e-16 ***
W:Age 332.9 8 < 2.2e-16 ***
---
Signif.
2006 Jun 30
2
Query : Chi Square goodness of fit test
I want to calculate chi square test of goodness of fit to test,
Sample coming from Poisson distribution.
please copy this script in R & run the script
The R script is as follows
########################## start
#########################################
No_of_Frouds<-
c(4,1,6,9,9,10,2,4,8,2,3,0,1,2,3,1,3,4,5,4,4,4,9,5,4,3,11,8,12,3,10,0,7)
N <- length(No_of_Frouds)
# Estimation of
2009 Feb 09
2
R equivalent of SAS Cochran-Mantel-Haenszel tests?
In SAS, for a two-way (or 3-way, stratified) table, the CMH option in
SAS PROC FREQ gives
3 tests that take ordinality of the factors into account, for both
variables, just the column variable
or neither. Is there an equivalent in R?
The mantelhaen.test in stats gives something quite different (a test of
conditional independence for
*nominal* factors in a 3-way table).
e.g. I'd like to
2008 Sep 30
2
weird behavior of drop1() for polr models (MASS)
I would like to do a SS type III analysis on a proportional odds logistic
regression model. I use drop1(), but dropterm() shows the same behaviour. It
works as expected for regular main effects models, however when the model
includes an interaction effect it seems to have problems with matching the
parameters to the predictor terms. An example:
library("MASS");
options(contrasts =
2003 Dec 04
3
Operating environment for *
Hi all,
I've got some questions to post in regard to running asterisk in a
production-grade environment, specifically targeting high-density IVR
applications. No VoIP involved, just straight PSTN -> * and perhaps the
occasional outdials or agent-based predictive dialing.
1) Which user would you run * under?
2) What other security-related issues do you have to resolve?
3) How do you handle
2008 Jan 17
1
'simulate.p.value' for goodness of fit
R Help on 'chisq.test' states that
"if 'simulate.p.value' is 'TRUE', the p-value is computed by Monte
Carlo simulation with 'B' replicates.
In the contingency table case this is done by random sampling from
the set of all contingency tables with given marginals, and works
only if the marginals are positive...
In the
2006 May 07
3
Needle + Rails - IoC
Hi,
I''m looking for past efforts to integrate Rails and Needle. I am
thinking of doing it myself but would be interested in seeing what
others have done before.
If there are examples of other IoC frameworks being used with Ruby I''d
be interested in hearing about them too. I find IoC to be a helpful
concept in general and, having glanced at a few existing Rails app.s, I
2011 May 08
1
Hosmer-Lemeshow 'goodness of fit'
I'm trying to do a Hosmer-Lemeshow 'goodness of fit' test on my logistic
regression model.
I found some code here:
http://sas-and-r.blogspot.com/2010/09/example-87-hosmer-and-lemeshow-goodness.html
The R code is above is a little complicated for me but I'm having trouble
with my answer:
Hosmer-Lemeshow: p=0.6163585
le Cessie and Houwelingen test (Design library): p=0.2843620
2007 Nov 22
5
testing independence of categorical variables
hi,
is there a way of calculating of measuring dependence between two
categorical variables. i tried using the chi square test to test for
independence but i got error saying that the lengths of the two
vectors don't match. Suppose X and Y are two factors. X has 5 levels
and Y has 7 levels. This is what i tried doing
>temp<-chisq.test(x,y)
but got error "the lengths of the two