As Michael suggests carefully read the help file (type ?chisq.test to bring up 
the page) and match all the elements of your command with the elements listed 
on the help page.

You do not need to use attach(chicken) given the code you are using and using 
attach(data)  is generally considered bad practice. The two equations below are 
equivalent and the second is better practice in R.

anova(lm(chicken$ration~chicken$weight)) # your code

anova(lm(ration ~ weight, data = chickens)) # cleaner code.

Also have a look at ?with

I'd suggest having a look at 
http://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-ex
 and/or http://adv-r.had.co.nz/Reproducibility.html for some ideas on how to 
form questions and supply sample data to R-help.

You are posting from nabble which does not supply any context for the help 
list.  If you are going to post here regularly I think everyone would be 
grateful if you post directly to R-help from a mail program. Very few people 
here use nabble and it is generally considered something of a curse.

Good luck on the quizz


John Kane
Kingston ON Canada


> -----Original Message-----
> From: 2hanl...@naver.com
> Sent: Fri, 25 Sep 2015 04:44:59 -0700 (PDT)
> To: r-help@r-project.org
> Subject: [R] There is an error when I performed chisquare and postanova
> test...:(
> 
> I am studying for a quiz and while I was solving two problems, an error
> occured.
> a) So the problem is we want to test if the block program makes a
> difference
> in retention at α = 1%
> (which is the significance level)
> This is the code I used to perform chisquare test.
> My solution:
> blockprogram <- matrix(c(18,15,5,8,4,10,5,7,18,10), nrow=2, byrow=T)
> colnames(blockprogram) <- c("1 yr","2 yr","3 yr","4 yr","5+ yrs")
> rownames(blockprogram) <- c("Non-Block","Block")
> chisq.test(blockprogram, conf.level=0.99) ==> This is the part where I
> can't
> run..
> chisq.test(blockprogram, conf.level=0.99)$observed
> chisq.test(blockprogram, conf.level=0.99)$expected
> So my question is is it the *conf.level=0.99* where it is wrongly used?
> 
> b)I was able to run the one way anova but wasn't able to run on the
> tukey's
> test. I seriously do not know what went wrong... So, this is the original
> problem:
> The data set chicken.csv contains weights of chickens which are given 1
> of 3
> different food rations. Perform an ANOVA procedure to determine if the
> weights of the chickens are significantly affected by the food rations
> they
> are provided. In case a significant effect exists, perform a Tukey HSD
> post-hoc procedure to identify under which ration the chickens will be
> heaviest. Use a 5% level of significance.
> 
> SO here's the code I used to perform:
> chicken <- read.csv("C:/Users/Win/Desktop/chicken.csv")
> attach(chicken)
> anova(lm(chicken$ration~chicken$weight))
> anova.ration <- aov(chicken$ration~chicken$weight)
> *posthoc.ration <- TukeyHSD(anova.ration, 'weight', conf.level=0.95) =>
> This
> is the part where I wasn't able to run :(*
> tapply(ration,weight, mean, na.rm=T)
> plot(posthoc.weight)
> 
> Thanks!
> 
> 
> 
> 
> --
> View this message in context:
> http://r.789695.n4.nabble.com/There-is-an-error-when-I-performed-chisquare-and-postanova-test-tp4712770.html
> Sent from the R help mailing list archive at Nabble.com.
> 
> ______________________________________________
> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide
> http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.

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