similar to: why my code is not computing significance level and power correctly

hie Im trying to calculate the power of the logrank test for different values of rho .I was just wandering whether the following programme would do it. any suggestions are welcome s=50 number=1 count1=0;count2=0;count3=0;count4=0;count5=0;count6=0;count7=0;count7=0; count8=0;count9=0 while(s!=0){ n=20 n1=n/2

my program given below can some one make it presentable. I trying to simulate survival data and calculate the power. I think i could have done better. s=10 number=0 count1=0;count2=0;count3=0;count4=0;count5=0;count6=0;count7=0;count8=0; count9=0; count11=0;count22=0;count33=0;count44=0;count55=0;count66=0;count77=0; count88=0;count99=0; while(s!=0){ n=100 n1=n/2 n2=n/4

for example, an expression such as chisq(df=1,ncp=0) ? thanks -- View this message in context: http://www.nabble.com/how-to-calculate-chisq-value-in-R-tp15338943p15338943.html Sent from the R help mailing list archive at Nabble.com.

Hi all, I know that I can run an one way ANOVA on the absolute residual values to check the assumption of equal variances: model<- lm(y~x) summary(lm(abs(model$resid~x))) What if I have two factors? As far as I know I have to check this assumption on very factor/level combination. So if I have 3 factors with three levels, I would have to test 9 factor/level combinations. Here comes my

I am trying to use Levene's test (of package car), but I do not understand quite well how to use it. '?levene.test' does not unfortunately provide any example. My data are in a data frame and correspond to 1 factor plus response. Could someone please give me an example about how to use the command levene.test(y, group) Thanks in advance, marta -- View this message in

Hi, I have been unable to find how to go about changing the significance level in R for hypothesis testing and regression analysis. R has a default setting to alpha=95% (a significance level of 95%), but I want to be able to decrease or increase this level when necessary. If you could give me instructions on how to change the significance level in R for hypothesis testing and regression analysis

Hello all, I am low down on the learning curve of R but so far I have had little trouble using most of the packages. However, recently I have run into a wall when it comes to bootstrapping a Levene's test (from the car package) and thought you might be able to help. I have not been able to find R examples for the "boot" package where the test statistic specifically uses a

Hi All, is there Levene' test in R ? If not ,Could you give me some advice about Levene test with R? Thanks a lot! I am waiting for yours.

Im doing test on my sample using 1-sample Kolmogorov-smirnov test(poisson distribution) to specify my sample obtain avalanche effect. before i can compare my D value with the critical value(Dn, alpha), i have to specify which level of significance to use (eg. alpha = 0.01, 0.05, etc) and i don't understand, why is it related to the probability that the hypothesis will be rejected when it is in

Hello R community, I am looking for a robust test for equality of variances that can take observation weights. I realize I can do the F-test with weighted variances, but I've read that this test is not very robust. So I thought about maybe adding a "weights" argument to John Fox's code for the Levene Test (in the "car" library, "levene.test"), substituting

Dear All I am trying to use Levene's test (of package car), but I do not understand quite well how to use it. '?levene.test' does not unfortunately provide any example. My data are in a data frame and correspond to 4 factors plus response. Could someone please give me an example about how to use the command levene.test(y, group) ? Thanks in advance, Paul

Hello, I notice that when I do Levene's test to test equality of variances across levels of a factor, I get different answers in R and SPSS 16. e.g.: For the chickwts data, in R, levene.test(weight, feed) gives F=0.7493, p=0.5896. SPSS 16 gives F=0.987, p=0.432 Why this difference? Which one should I believe? (I would like to believe R :) Ravi -- View this message in context:

Hallo! I just started working with R to do the statistical analyses for my diploma thesis. I got two sets of data. Both contain repeated measures. One has only one within-subject factor with four levels. The other has one within-subject factor with two levels and one between-factor with two levels. I want to compute a Mauchly test for both sets and a Levene test for the second set. I

Dear Mariano, See the function leveneTest() in the car package. I hope that this helps, John ----------------------------- John Fox, Professor Emeritus McMaster University Hamilton, Ontario, Canada Web: socialsciences.mcmaster.ca/jfox/ > -----Original Message----- > From: R-help [mailto:r-help-bounces at r-project.org] On Behalf Of Marcelo > Mariano Silva > Sent: Monday, January

> From: Peter Dalgaard BSA <p.dalgaard at biostat.ku.dk> > Date: 01 Sep 2000 09:54:59 +0200 > > Prof Brian D Ripley <ripley at stats.ox.ac.uk> writes: Important omission: specification from Murray Jorgensen The test that I was thinking of basically does an anova on a modified response variable that is the absolute value of the difference between an observation

Hi R, Does the "step" function used to perform stepwise regression has the option to specify the entry/exit significance levels for the independent variables? (This is similar to the 'slentry' and 'slstay' option in 'Proc reg' of SAS.). Or do we have any other package which does the above? Thanks. Thanks and Regards, Shubha This e-mail may

Hi, All! To calculate Levene's Test for Homogeneity of Variance I use R Commander, and this is the output: > levene.test(Dataset$age, Dataset$sex) Levene's Test for Homogeneity of Variance Df F value Pr(>F) group 1 0.8739 0.3567 33 I am not sure what means "Pr(>F)"? Can anyone explain/translate this? Regards, Iurie Malai Department of Psychology and

I have struggled with compiling 2.0.5a on Solaris 2.6 with gcc version 2.8.1 for the last couple of weeks (not a high priority project) and decided to try a precompiled version just in case I was being stupid. Well, perhaps I'm stupider (is that a word) than I thought because I installed the package and I still cannot connect. I have read through the docs and tried more than a few

Has the Levene test of homogeneity of variance been implemented in any library in R? Thanks, Maurice Haynes National Institute of Child Health and Human Development Child and Family Research Section 6705 Rockledge Drive Bethesda, MD 20892 Voice: 301-496-8180 Fax: 301-496-2766 E-Mail: mh192j at nih.gov

Hello, I am searching for the classic Levene test of variances in R but I don't find the function. Is there any command or do I have to programm the test by myself? Does anybody know? Help would be fine because R is very new to me. S.Zank [[alternative HTML version deleted]]