Displaying 20 results from an estimated 10000 matches similar to: "Chi-square Goodness of Fit Test"
2011 Dec 19
2
On Corrections for Chi-Sq Goodness of Fit Test
TOPIC
My question regards the philosophy behind how R implements corrections to chi-square statistical tests. At least in recent versions (I'm using 2.13.1 (2011-07-08) on OSX 10.6.8.), the chisq.test function applies the Yates continuity correction for 2 by 2 contingency tables. But when used as a goodness of fit test (GoF, aka likelihood ratio test), chisq.test does not appear to implement
2010 Jul 07
1
Different goodness of fit tests leads to contradictory conclusions
I am trying to test goodness of fit for my legalistic regression using several options as shown below. Hosmer-Lemeshow test (whose function I borrowed from a previous post), Hosmer–le Cessie omnibus lack of fit test (also borrowed from a previous post), Pearson chi-square test, and deviance test. All the tests, except the deviance tests, produced p-values well above 0.05. Would anyone please
2009 Feb 04
3
chi squared goodness of fit test with R
Dear R users,
I am a master student in Mathematics and I am writing my thesis in
statistics. I need to use R and unfortunately I do not have any experience
with a computer program. Could you please help me about chi squared goodness
of fit test with R? In R-help website I saw a message about how to do that
but I do not know how to cut the data into bins and calculate the expected
numbers in each
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
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
2010 Mar 10
2
Test chi cuadrado de bondad de ajuste
Hola,
con vistas a docencia, me gustaría saber si hay alguna librería que
haga el test de la chi cuadrado para variables continuas, que no sean
la normal.
Lo encontré para variables discretas y para la normal. También,
obviamente, se puede hacer un pequeño programa que lo calcule "como a
mano", pero a los alumnos les obliga a entrar en detalles de
programación... :-/
La idea sería
2024 Sep 17
0
Degree of freedom issue on chi-square test of goodness of fit
I am running chi-square test of goodness of fit, the observation data was
well groupped to observation freq. I assume the data obey the normal
distribution N(? ?^2), while ? and ?^2 are unknown. So I use their
estimation. Consequently, I calculated out the probabilities and input in
vector p
>x<-c(6,13,14,27,25,19,10,6) #observation freq>p<-c(0.0505, 0.0874, 0.1533, 0.2088, 0.2088,
2010 Sep 01
1
[Q] Goodness-of-fit test of a logistic regression model using rms package
Hello,
I was looking for a way to evaluate the goodness-of-fit of a logistic regression model. After googling, I found that I could use "resid(fit, 'gof')" method implemented in the rms package. However, since I am not used to the "le Cessie-van Houwelingen normal test statistic," I do not know which statistic from the returned from the "resid(fit,
2008 Sep 08
0
Poisson Distribution - Chi Square Test for Goodness of Fit
Dear R-help,
Chi Square Test for Goodness of Fit
Problem Faced :
I have got a discrete data
as given below (R script)
No_of_Frauds <-c 1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,2,1,2,2,2,1,1,2,1,1,1,1,4,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,2,1,1,1,1,1,1,1,3,2,1,1,1,2,1,1,2,1,1,1,1,1,2,1,3,1,2,1,2,14,2,1,1,38,3,3,2,44,1,4,1,4,1,2,2,1,3)
I am trying to fit
2008 Aug 29
0
Problem with Poisson - Chi Square Goodness of Fit Test - New Mail
Dear R-help,
?
?
Chi Square Test for Goodness of Fit
?
I have got a discrete data
as given below (R script)
?
No_of_Frauds<-c(1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,2,1,2,2,2,1,1,2,1,1,1,1,4,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,2,1,1,1,1,1,1,1,3,2,1,1,1,2,1,1,2,1,1,1,1,1,2,1,3,1,2,1,2,14,2,1,1,38,3,3,2,44,1,4,1,4,1,2,2,1,3)
?
I am trying to fit Poisson
distribution to
2008 Aug 29
0
Poisson Distribution - problem with Chi Square Goodness of Fit test
Chi Square Test for Goodness of Fit
I have got a discrete data
as given below (R script)
No_of_Frauds<-c(1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,2,1,2,2,2,1,1,2,1,1,1,1,4,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,2,1,1,1,1,1,1,1,3,2,1,1,1,2,1,1,2,1,1,1,1,1,2,1,3,1,2,1,2,14,2,1,1,38,3,3,2,44,1,4,1,4,1,2,2,1,3)
I am trying to fit Poisson
distribution to this data using R.
2008 Aug 29
0
Please ignore earlier mail - [ Poisson - Chi Square test for Goodness of Fit]
Dear R-help,
?
?
Chi Square Test for Goodness of Fit
?
I have got a discrete data
as given below (R script)
?
No_of_Frauds<-c(1,1,1,1,1,1,1,1,1,2,1,1,1,1,1,1,2,1,2,2,2,1,1,2,1,1,1,1,4,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,5,1,2,1,1,1,1,1,1,1,3,2,1,1,1,2,1,1,2,1,1,1,1,1,2,1,3,1,2,1,2,14,2,1,1,38,3,3,2,44,1,4,1,4,1,2,2,1,3)
?
I am trying to fit Poisson
2010 Feb 14
4
Problem in performing goodness of fit test in R.
I am trying to perform goodness of fit test using R. I am using this website http://wiener.math.csi.cuny.edu/Statistics/R/simpleR/stat013.html for help. However, I am unable to carry out the test successfully. My code follows. It is taken from the website just mentioned.
freq=c(22,21,22,27,22,36) # frequencies obtained after rolling the dice 150 times.
prob=c(1,1,1,1,1,1)/6 # specify expected
2008 Apr 09
1
chi-square test
Hi R-users,
I would like to find the goodness of fit using Chi-suare test for my data below:
xobs=observed data, xtwe=predicted data using tweedie, xgam=predicted data using gamma
> xobs <- c(223,46,12,5,7,17)
> xtwe <- c(217.33,39,14,18.33,6.67,14.67)
> xgam <- c(224.67,37.33,12.33,15.33,5.33,15)
> chisq.test(xobs, xtwe = xtwe, rescale.p = TRUE)
Error in chisq.test(xobs,
2008 Nov 26
2
Chi-Square Test Disagreement
I was asked by my boss to do an analysis on a large data set, and I am
trying to convince him to let me use R rather than SPSS. I think Sweave
could make my life much much easier. To get me a little closer to this
goal, I ran my analysis through R and SPSS and compared the resulting
values. In all but one case, they were the same. Given the matrix
[,1] [,2]
[1,] 110 358
[2,] 71 312
[3,]
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
2005 Apr 19
1
chi-square test
a warning message appears when i use the chisq.test ,but it doesnt
appear everytime, why?
"Warning message:
Chi-squared approximation may be incorrect in:
chisq.test(matrix(c(20.1, 18.5, 2.6, 32.9, 23.5, 5.4), nc = 2)) "
why does the warning message appear, please?
Thank you very much
here is the data which I have tried appear and not appear warning
message
have warning message
2011 Sep 27
2
Pearson chi-square test
Dear all,
I have some trouble understanding the chisq.test function.
Take the following example:
set.seed(1)
A <- cut(runif(100),c(0.0, 0.35, 0.50, 0.65, 1.00), labels=FALSE)
B <- cut(runif(100),c(0.0, 0.25, 0.40, 0.75, 1.00), labels=FALSE)
C <- cut(runif(100),c(0.0, 0.25, 0.50, 0.80, 1.00), labels=FALSE)
x <- table(A,B)
y <- table(A,C)
When I calculate the test statistic by hand
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
2011 Apr 22
1
Create 2x2 table from summary data and run chi square test.
R 2.12
windows 7
I am summary data that I would like to make into a 2x2 table representing counts positive vs. negative counts:
28/289 20/276
My table should look something like the following:
group1 group2
Positive 28 20
Negative 289 276
How can a (1) create the 2x2 table
(2) run a chi square test on the table?
I have tried the following code, but I