Dear All, I want to test a hypothesis in R by using student' t-test (P-values). The hypothesis is that model A produces lesser error than model B at ten stations. Obviously, Null Hypothesis (H0) is that the error produces by model A is not lower than model B. The error magnitudes are #model A> dput(mA)c(36.1956086452583, 34.9996207622861, 36.435733025221, 37.2003157636202, 36.1318687775115, 37.164132533536, 35.2028759357069, 36.7719835944373, 38.3861425339751, 37.4174132119744) #model B> dput(mB)c(39.7655211768704, 40.1730916643841, 39.3699055738618, 39.401619831763, 41.1218634441457, 39.1968630742826, 40.5265825061639, 40.4674956975404, 40.5954427072364, 41.4875529130543) Now can I test my hypothesis in R? Thankyou very much in Advance, Eliza [[alternative HTML version deleted]]
Hello, Try ?t.test t.test(mA, mB, alternative = "greater") Hope this helps, Rui Barradas ? Citando Eliza Botto <eliza_botto at outlook.com>:> Dear All, > I want to test a hypothesis in R by using student' t-test (P-values). > The hypothesis is that model A produces lesser error than model B at > ten stations. Obviously, Null Hypothesis (H0) is that the error > produces by model A is not lower than model B. > The error magnitudes are > > #model A >> dput(mA) > > c(36.1956086452583, 34.9996207622861, 36.435733025221, > 37.2003157636202, 36.1318687775115, 37.164132533536, > 35.2028759357069, 36.7719835944373, 38.3861425339751, > 37.4174132119744) > #model B >> dput(mB) > > c(39.7655211768704, 40.1730916643841, 39.3699055738618, > 39.401619831763, 41.1218634441457, 39.1968630742826, > 40.5265825061639, 40.4674956975404, 40.5954427072364, > 41.4875529130543) > > Now can I test my hypothesis in R? > Thankyou very much in Advance, > Eliza > ? ? ? ? [[alternative HTML version deleted]] > > ______________________________________________ > R-help at 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.htmland provide commented, > minimal, self-contained, reproducible code.? [[alternative HTML version deleted]]
Thnx Rui,
Just one point though
Should it be alternative="greater" or "less"? Since
alternative hypothesis is that model A produced less error.
regards,
Eliza
Date: Wed, 23 Mar 2016 20:44:20 +0000
From: ruipbarradas at sapo.pt
To: eliza_botto at outlook.com
CC: r-help at r-project.org
Subject: Re: [R] test hypothesis in R
Hello,
Try
?t.test
t.test(mA, mB, alternative = "greater")
Hope this helps,
Rui Barradas
Citando Eliza Botto <eliza_botto at outlook.com>:
Dear All,
I want to test a hypothesis in R by using student' t-test (P-values).
The hypothesis is that model A produces lesser error than model B at ten
stations. Obviously, Null Hypothesis (H0) is that the error produces by model A
is not lower than model B.
The error magnitudes are
#model A
dput(mA)
c(36.1956086452583, 34.9996207622861, 36.435733025221, 37.2003157636202,
36.1318687775115, 37.164132533536, 35.2028759357069, 36.7719835944373,
38.3861425339751, 37.4174132119744)
#model B
dput(mB)
c(39.7655211768704, 40.1730916643841, 39.3699055738618, 39.401619831763,
41.1218634441457, 39.1968630742826, 40.5265825061639, 40.4674956975404,
40.5954427072364, 41.4875529130543)
Now can I test my hypothesis in R?
Thankyou very much in Advance,
Eliza
[[alternative HTML version deleted]]
______________________________________________
R-help at 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.htmland
provide commented, minimal, self-contained, reproducible code.
[[alternative HTML version deleted]]
> On Mar 23, 2016, at 1:44 PM, ruipbarradas at sapo.pt wrote: > > Hello, > > Try > > ?t.test > t.test(mA, mB, alternative = "greater") > > Hope this helps, > > Rui Barradas > > > Citando Eliza Botto <eliza_botto at outlook.com>: > >> Dear All, >> I want to test a hypothesis in R by using student' t-test (P-values). >> The hypothesis is that model A produces lesser error than model B at >> ten stations. Obviously, Null Hypothesis (H0) is that the error >> produces by model A is not lower than model B.NOT "obviously". You only get to do one-sided tests when the scientific question would not allow the possibility of a departure to "the other side". Two-sided tests are the norm in scientific literature, often to the experimenter's distress when they haven't done a thoughtful (non-optimistic) power analysis and their results are inconclusive as a result. Your hypothesis _should_ have been constructed _before_ you saw the data. That is if you want to be an ethical scientist.>> The error magnitudes are >> >> #model A >>> dput(mA) >> >> c(36.1956086452583, 34.9996207622861, 36.435733025221, >> 37.2003157636202, 36.1318687775115, 37.164132533536, >> 35.2028759357069, 36.7719835944373, 38.3861425339751, >> 37.4174132119744) >> #model B >>> dput(mB) >> >> c(39.7655211768704, 40.1730916643841, 39.3699055738618, >> 39.401619831763, 41.1218634441457, 39.1968630742826, >> 40.5265825061639, 40.4674956975404, 40.5954427072364, >> 41.4875529130543)Those are not models. They are just vectors of numbers. And they seem unlikely to be residual errors of a linear model since they are not centered on zero. I doubt there is enough in your presentation for a sensible comment on the proper analysis. -- David.>> >> Now can I test my hypothesis in R? >> Thankyou very much in Advance, >> Eliza >> [[alternative HTML version deleted]] >> >> ______________________________________________David Winsemius Alameda, CA, USA