Displaying 20 results from an estimated 20000 matches similar to: "two sample chi-squared test"
2006 Dec 02
1
Chi-squared approximation may be incorrect in: chisq.test(x)
I am getting "Chi-squared approximation may be incorrect in:
chisq.test(x)" with the data bleow.
Frequency distribution of number of male offspring in families of size 5.
Number of Male Offspring N
0 518
1 2245
2 4621
3 4753
4 2476
5
2005 May 26
1
Chi Square Test on two groups of variables
Dear R help
I have been trying to conduct a chi square test on two groups of variables
to test whether there is any relationship between the two sets of variables
chisq.test(oxygen, train)
Pearson's Chi-squared test
data: oxygen
X-squared = 26.6576, df = 128, p-value = 1
> chisq.test(oxygen)
Pearson's Chi-squared test
data: oxygen
X-squared = 26.6576, df = 128,
2005 Nov 24
2
Chi-squared test
Hello,
I'm trying to calculate a chi-squared test to see if my data are
different from the theoretical distribution or not:
chisq.test(rbind(c(79, 52, 69, 71, 82, 87, 95, 74, 55, 78, 49,
60),c(80,80,80, 80, 80, 80, 80, 80, 80, 80, 80, 80)))
Pearson's Chi-squared test
data: rbind(c(79, 52, 69, 71, 82, 87, 95, 74, 55, 78, 49, 60), c(80,
80, 80, 80, 80, 80, 80, 80, 80, 80, 80,
2007 Feb 26
1
Chi Square with two tab-delimited text files
Hi,
I want to do a chi square test and I have two tab delimited text files with
Expected and Observed values to compare. Each file contains only the values
and are 48 rows by 116 columns. I have managed to do something with them,
but I don't think it is right as I got a p value of 1. In this case I used
the read.table() function to read the values from the files. But I don't
know if
2008 Jan 15
2
In chisq.test(x) : Chi-squared approximation may be incorrect
Hello,
I received the following warning when running chi-square;
n Is there a way to catch the 'error' code of 'warning' after run
chisq.test(x)?
n What does this error mean?
Thank you for your help.
[[alternative HTML version deleted]]
2001 Dec 18
4
chi-squared test
I don't quite understand the difference between the two methods for
performing a chi-squared test on contingency tables: summary(table())
and chisq.test()
They may different results. E.g.:
aa <- gl(2, 10)
bb <- as.factor(c(1,2,2,2,1,2,1,2,2,2,1,2,2,2,1,1,1,2,1,1))
aa <- c(aa, aa)
bb <- c(bb, bb)
table(aa, bb)
summary(table(aa, bb))
chisq.test(aa, bb)
Could somebody give me
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
2003 Apr 22
4
fisher exact vs. simulated chi-square
Dear All,
I have a problem understanding the difference between the outcome of a
fisher exact test and a chi-square test (with simulated p.value).
For some sample data (see below), fisher reports p=.02337. The normal
chi-square test complains about "approximation may be incorrect",
because there is a column with cells with very small values. I
therefore tried the chi-square with
2012 Dec 03
4
Chi-squared test when observed near expected
Dear UseRs,
I'm running a chi-squared test where the expected matrix is the same as the
observed, after rounding. R reports a X-squared of zero with a p value of
one. I can justify this because any other result will deviate at least as
much from the expected because what we observe is the expected, after
rounding. But the formula for X-squared, sum (O-E)^2/E gives a positive
value. What
2003 Apr 11
1
Pearson's Chi-squared Test
How i can perform a Pearson's Chi-squared Test in this data set:
| Outcome
-----------------+-----------+----------------------------------+
Treatment | Sex | None |Some | Marked | Total
-----------------+------------+--------+--------+-------------+
Active | Female | 6 | 5 | 16 | 27
2010 Dec 29
1
Problem applying Chi-square in R and Cochran's Recommendations
Sir,
I have a problem here while applying chisquare test to the following Data (
below the subject of this mail) ...when I wanted to test the significance
using three different free statistical packages, here R, EpiInfo and
OpenEpi.
*Only OpenEpi accepts the test based on Cochran's Recommendations. *
R says " chi squared approximation may be incorrect."
Does it mean the same as
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 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
2011 Oct 11
3
Chi-Square test and survey results
An organization has asked me to comment on the validity of their
recent all-employee survey. Survey responses, by geographic region,
compared
with the total number of employees in each region, were as follows:
> ByRegion
All.Employees Survey.Respondents
Region_1 735 142
Region_2 500 83
Region_3 897 78
2011 Jan 06
1
need help for chi-squared test
I've got a dataset which looks like this in the beginning:
cbr dust smoking expo
1 0 0.20 1 5
2 0 0.25 1 4
3 0 0.25 1 8
4 0 0.25 1 4
5 0 0.25 1 4
(till no. 1240, anyway, a huge set)
I have to analyse cbr and smoking, I know it works with chisq.test() for the
whole set, but I only need cbr and smoking, and I
2011 Mar 04
1
Question in Chi-squared test, can I do it with percentage data?
Hi all,
I know Chi-squared test can be done with the frequency data by R function
"chisq.test()", but I am not sure if it can be applied to the percentage
data ? The example of my data is as follow:
#############################################
KSL MHL MWS CLGC LYGC
independent (%) 96.22 92.18 68.54 93.80 85.74
2009 Jun 03
1
Validity of Pearson's Chi-Square for Large Tables
Is Pearson's Chi-Square test for contingency tables asymptotically unbiased
for large tables (large degrees of freedom) regardless of the expected
values in each cell? The rule of thumb is that Pearson's Chi-square should
not be used when large numbers of cells have expected values < 5. However,
I compared the results on 4x4 contingency tables for R's chisq.test using
chi-square
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,]
2011 Jan 02
1
Clusteranalysis Chi-square test and SingleLinkage
Hi
The short version of my questions is this:
How can I run a chi-square test over a matrix (table) to get the distanaces
between rows and then run a SingleLinkage (or other fusion algorithm over
the resulting table?
------------
The long-version of my question:
My data consists of different data of different countries so I have stuff
like how many people can read, write in X,Y,Z countries
2007 Nov 20
1
Problem with code for bootstrapping chi square test with count data
Hi,
I'd like some advice on bootstrapping in R.
I have a species x with 20 individuals and a factor containing 0 and 1's
(in this case 5 zeros and 15 ones). I want to compare the frequency of
the occurrence of 1 with a probability value. This code seems to work to
do this in R.
attach(test)
p <- c(0.5272, (1-0.5272))
sp1_1 <- length(subset(x, x==1))
sp1_0 <- length(subset(x,