Re: [R] general question on binomial test / sign test

2010-09-03 Thread Greg Snow
gt; > > > -- > > Gregory (Greg) L. Snow Ph.D. > > Statistical Data Center > > Intermountain Healthcare > > greg.s...@imail.org > > 801.408.8111 > > > > > >> -----Original Message- > >> From: Ted Harding [mailto:ted.hard...@manc

Re: [R] general question on binomial test / sign test

2010-09-03 Thread Bert Gunter
iginal Message- >> From: Ted Harding [mailto:ted.hard...@manchester.ac.uk] >> Sent: Thursday, September 02, 2010 3:59 PM >> To: Greg Snow >> Cc: r-help@r-project.org; Kay Cecil Cichini >> Subject: Re: [R] general question on binomial test / sign test >> &

Re: [R] general question on binomial test / sign test

2010-09-03 Thread Greg Snow
Sent: Thursday, September 02, 2010 3:59 PM > To: Greg Snow > Cc: r-help@r-project.org; Kay Cecil Cichini > Subject: Re: [R] general question on binomial test / sign test > > On 02-Sep-10 18:01:55, Greg Snow wrote: > > Just to add to Ted's addition to my response. I

Re: [R] general question on binomial test / sign test

2010-09-02 Thread Ted Harding
On 02-Sep-10 18:01:55, Greg Snow wrote: > Just to add to Ted's addition to my response. I think you are moving > towards better understanding (and your misunderstandings are common), > but to further clarify: > [Wise words about P(A|B), P(B|A), P-values, etc., snipped] > > The real tricky bit abo

Re: [R] general question on binomial test / sign test

2010-09-02 Thread Greg Snow
ta Center > > Intermountain Healthcare > > greg.s...@imail.org > > 801.408.8111 > > > > > >> -Original Message- > >> From: r-help-boun...@r-project.org [mailto:r-help-boun...@r- > >> project.org] On Behalf Of Kay Cecil Ci

Re: [R] general question on binomial test / sign test

2010-09-02 Thread David Winsemius
Cichini Sent: Thursday, September 02, 2010 6:40 AM To: ted.hard...@manchester.ac.uk Cc: r-help@r-project.org Subject: Re: [R] general question on binomial test / sign test thanks a lot for the elaborations. your explanations clearly brought to me that either binom.test(1,1,0.5,"two-sided

Re: [R] general question on binomial test / sign test

2010-09-02 Thread Greg Snow
ember 02, 2010 6:40 AM > To: ted.hard...@manchester.ac.uk > Cc: r-help@r-project.org > Subject: Re: [R] general question on binomial test / sign test > > > thanks a lot for the elaborations. > > your explanations clearly brought to me that either > binom.test(1,1,0.5,"

Re: [R] general question on binomial test / sign test

2010-09-02 Thread Kay Cichini
..i'd like to add that i actually wanted to test the location of differences of paired samples coming from an non-normal asymetric distribution. the alternative hypothesis was that negative differences are more often than in 0.5 of all cases. thus i tested (x=nr.diff.under.0,n=all.diffs,0.5,altern

Re: [R] general question on binomial test / sign test

2010-09-02 Thread Kay Cecil Cichini
thanks a lot for the elaborations. your explanations clearly brought to me that either binom.test(1,1,0.5,"two-sided") or binom.test(0,1,0.5) giving a p-value of 1 simply indicate i have abolutely no ensurance to reject H0. considering binom.test(0,1,0.5,alternative="greater") and binom.

Re: [R] general question on binomial test / sign test

2010-09-02 Thread Ted Harding
You state: "in reverse the p-value of 1 says that i can 100% sure that the estimate of 0.5 is true". This is where your logic about significance tests goes wrong. The general logic of a singificance test is that a test statistic (say T) is chosen such that large values represent a discrepancy betw

Re: [R] general question on binomial test / sign test

2010-09-02 Thread Kay Cecil Cichini
i test the null that the coin is fair (p(succ) = p(fail) = 0.5) with one trail and get a p-value of 1. actually i want to proof the alternative H that the estimate is different from 0.5, what certainly can not be aproven here. but in reverse the p-value of 1 says that i can 100% sure that t

Re: [R] general question on binomial test / sign test

2010-09-01 Thread Greg Snow
Try thinking this one through from first principles, you are essentially saying that your null hypothesis is that you are flipping a fair coin and you want to do a 2-tailed test. You then flip the coin exactly once, what do you expect to happen? The p-value of 1 just means that what you saw wa