Please let me ask you another quick question. I have results for e coli, and am trying to get 95% CI with the sd (1.783956). I got the result from another tool as (1.21, 3.42). But, I like to verify it with R. What function do you use for this?> e.coli=c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) > sd(e.coli, na.rm = FALSE)[1] 1.783956 Sorry for the newbie question. thx much ej
Ethan Johnsons wrote:> Please let me ask you another quick question. > I have results for e coli, and am trying to get 95% CI with the sd (1.783956). > I got the result from another tool as (1.21, 3.42). > But, I like to verify it with R. What function do you use for this? > >> e.coli=c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) >> sd(e.coli, na.rm = FALSE) > [1] 1.783956 > > Sorry for the newbie question.e.coli <- c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) library(nlme) mod1 <- gls(e.coli ~ 1) intervals(mod1) Approximate 95% confidence intervals Coefficients: lower est. upper (Intercept) 24.16206 25.53333 26.90460 attr(,"label") [1] "Coefficients:" Residual standard error: lower est. upper 1.204986 1.783956 3.417651> thx much > > ej > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > 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.-- Chuck Cleland, Ph.D. NDRI, Inc. 71 West 23rd Street, 8th floor New York, NY 10010 tel: (212) 845-4495 (Tu, Th) tel: (732) 512-0171 (M, W, F) fax: (917) 438-0894
Thx so much, Chuck. R is a reallt sweet tool to use.. I can try many things with i.e. intervals (gls(e.coli ~ 1), level=0.90). It is a great help. ej On 10/19/06, Chuck Cleland <ccleland at optonline.net> wrote:> Ethan Johnsons wrote: > > Please let me ask you another quick question. > > I have results for e coli, and am trying to get 95% CI with the sd (1.783956). > > I got the result from another tool as (1.21, 3.42). > > But, I like to verify it with R. What function do you use for this? > > > >> e.coli=c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) > >> sd(e.coli, na.rm = FALSE) > > [1] 1.783956 > > > > Sorry for the newbie question. > > e.coli <- c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) > library(nlme) > mod1 <- gls(e.coli ~ 1) > intervals(mod1) > > Approximate 95% confidence intervals > > Coefficients: > lower est. upper > (Intercept) 24.16206 25.53333 26.90460 > attr(,"label") > [1] "Coefficients:" > > Residual standard error: > lower est. upper > 1.204986 1.783956 3.417651 > > > thx much > > > > ej > > > > ______________________________________________ > > R-help at stat.math.ethz.ch mailing list > > 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. > > -- > Chuck Cleland, Ph.D. > NDRI, Inc. > 71 West 23rd Street, 8th floor > New York, NY 10010 > tel: (212) 845-4495 (Tu, Th) > tel: (732) 512-0171 (M, W, F) > fax: (917) 438-0894 > >
I thought of another interesting scenario, and I would just go ahead and ask this. I have a mean (i.e. 26.2) where the number of e coli samples is 250. The mean is already calculated, so it is a discrete value, not series. What fucntion can be used for the calc with CI i.e. 90%? thx much, ej On 10/19/06, Chuck Cleland <ccleland at optonline.net> wrote:> Ethan Johnsons wrote: > > Please let me ask you another quick question. > > I have results for e coli, and am trying to get 95% CI with the sd (1.783956). > > I got the result from another tool as (1.21, 3.42). > > But, I like to verify it with R. What function do you use for this? > > > >> e.coli=c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) > >> sd(e.coli, na.rm = FALSE) > > [1] 1.783956 > > > > Sorry for the newbie question. > > e.coli <- c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) > library(nlme) > mod1 <- gls(e.coli ~ 1) > intervals(mod1) > > Approximate 95% confidence intervals > > Coefficients: > lower est. upper > (Intercept) 24.16206 25.53333 26.90460 > attr(,"label") > [1] "Coefficients:" > > Residual standard error: > lower est. upper > 1.204986 1.783956 3.417651 > > > thx much > > > > ej > > > > ______________________________________________ > > R-help at stat.math.ethz.ch mailing list > > 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. > > -- > Chuck Cleland, Ph.D. > NDRI, Inc. > 71 West 23rd Street, 8th floor > New York, NY 10010 > tel: (212) 845-4495 (Tu, Th) > tel: (732) 512-0171 (M, W, F) > fax: (917) 438-0894 > >
Hi On 19 Oct 2006 at 13:19, Ethan Johnsons wrote: Date sent: Thu, 19 Oct 2006 13:19:40 -0400 From: "Ethan Johnsons" <ethan.johnsons at gmail.com> To: "Chuck Cleland" <ccleland at optonline.net> Copies to: r-help at stat.math.ethz.ch Subject: Re: [R] CI with sd> I thought of another interesting scenario, and I would just go ahead > and ask this. I have a mean (i.e. 26.2) where the number of e coli > samples is 250. The mean is already calculated, so it is a discrete > value, not series. > > What fucntion can be used for the calc with CI i.e. 90%?With some sd value and assuming normal distribution 26.2+qnorm(.95)*sd/sqrt(250) 26.2-qnorm(.95)*sd/sqrt(250) as you can find in statistical textbooks. But without having sd value? HTH Petr> > thx much, > > ej > > On 10/19/06, Chuck Cleland <ccleland at optonline.net> wrote: > > Ethan Johnsons wrote: > > > Please let me ask you another quick question. > > > I have results for e coli, and am trying to get 95% CI with the sd > > > (1.783956). I got the result from another tool as (1.21, 3.42). > > > But, I like to verify it with R. What function do you use for > > > this? > > > > > >> e.coli=c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) > > >> sd(e.coli, na.rm = FALSE) > > > [1] 1.783956 > > > > > > Sorry for the newbie question. > > > > e.coli <- c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) > > library(nlme) > > mod1 <- gls(e.coli ~ 1) > > intervals(mod1) > > > > Approximate 95% confidence intervals > > > > Coefficients: > > lower est. upper > > (Intercept) 24.16206 25.53333 26.90460 > > attr(,"label") > > [1] "Coefficients:" > > > > Residual standard error: > > lower est. upper > > 1.204986 1.783956 3.417651 > > > > > thx much > > > > > > ej > > > > > > ______________________________________________ > > > R-help at stat.math.ethz.ch mailing list > > > 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. > > > > -- > > Chuck Cleland, Ph.D. > > NDRI, Inc. > > 71 West 23rd Street, 8th floor > > New York, NY 10010 > > tel: (212) 845-4495 (Tu, Th) > > tel: (732) 512-0171 (M, W, F) > > fax: (917) 438-0894 > > > > > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > 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.Petr Pikal petr.pikal at precheza.cz
Thank you so much. I see your point. ej On 10/20/06, Petr Pikal <petr.pikal at precheza.cz> wrote:> Hi > > On 19 Oct 2006 at 13:19, Ethan Johnsons wrote: > > Date sent: Thu, 19 Oct 2006 13:19:40 -0400 > From: "Ethan Johnsons" <ethan.johnsons at gmail.com> > To: "Chuck Cleland" <ccleland at optonline.net> > Copies to: r-help at stat.math.ethz.ch > Subject: Re: [R] CI with sd > > > I thought of another interesting scenario, and I would just go ahead > > and ask this. I have a mean (i.e. 26.2) where the number of e coli > > samples is 250. The mean is already calculated, so it is a discrete > > value, not series. > > > > What fucntion can be used for the calc with CI i.e. 90%? > > With some sd value and assuming normal distribution > > 26.2+qnorm(.95)*sd/sqrt(250) > 26.2-qnorm(.95)*sd/sqrt(250) > > as you can find in statistical textbooks. > > But without having sd value? > > HTH > Petr > > > > > > thx much, > > > > ej > > > > On 10/19/06, Chuck Cleland <ccleland at optonline.net> wrote: > > > Ethan Johnsons wrote: > > > > Please let me ask you another quick question. > > > > I have results for e coli, and am trying to get 95% CI with the sd > > > > (1.783956). I got the result from another tool as (1.21, 3.42). > > > > But, I like to verify it with R. What function do you use for > > > > this? > > > > > > > >> e.coli=c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) > > > >> sd(e.coli, na.rm = FALSE) > > > > [1] 1.783956 > > > > > > > > Sorry for the newbie question. > > > > > > e.coli <- c(27.5,24.6,25.3,28.7,23,26.8,24.7,24.3,24.9) > > > library(nlme) > > > mod1 <- gls(e.coli ~ 1) > > > intervals(mod1) > > > > > > Approximate 95% confidence intervals > > > > > > Coefficients: > > > lower est. upper > > > (Intercept) 24.16206 25.53333 26.90460 > > > attr(,"label") > > > [1] "Coefficients:" > > > > > > Residual standard error: > > > lower est. upper > > > 1.204986 1.783956 3.417651 > > > > > > > thx much > > > > > > > > ej > > > > > > > > ______________________________________________ > > > > R-help at stat.math.ethz.ch mailing list > > > > 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. > > > > > > -- > > > Chuck Cleland, Ph.D. > > > NDRI, Inc. > > > 71 West 23rd Street, 8th floor > > > New York, NY 10010 > > > tel: (212) 845-4495 (Tu, Th) > > > tel: (732) 512-0171 (M, W, F) > > > fax: (917) 438-0894 > > > > > > > > > > ______________________________________________ > > R-help at stat.math.ethz.ch mailing list > > 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. > > Petr Pikal > petr.pikal at precheza.cz > >