I cannot file suggestions on bugzilla, so writing here. As far as I can tell, the manual help page for ``sd`` ?sd does not explicitly mention that the formula for the standard deviation is the so-called "Bessel-corrected" formula (divide by n-1 rather than n). I suggest it should be stated near the top. I would also suggest (feature request!) that either - a population standard deviation formula, e.g. ``sdp`` or ``sd.p`` be made available (that would be my preference) or - the current ``sd`` be extended to accept a ``population=FALSE`` or ``sample=TRUE`` argument. Same for the variance. Excel, Calc, etc. offer these. Motivation: I encourage my students to use R rather than Python (which has picked up big time in recent years) on the grounds that it is easier to get started with and is specialized in statistics. But then there is no "population" formula for the standard deviation. And ``mode`` is not the mode they expect... (btw I suggest adding a ``modes`` function to the core) All things a beginner will look for in a stats software. Thanks for listening. And thanks for the great work! [[alternative HTML version deleted]]
> As far as I can tell, the manual help page for ``sd`` > > ?sd > > does not explicitly mention that the formula for the standard deviation is > the so-called "Bessel-corrected" formula (divide by n-1 rather than n).See Details, where it says "Details: Like 'var' this uses denominator n - 1. " ******************************************************************* This email and any attachments are confidential. Any use...{{dropped:8}}
Good day, It is implemented by the CRAN package multicon. The function is named popsd. But it does seem like something R should provide without creating a package dependency. -------------------------------------- Dario Strbenac University of Sydney Camperdown NSW 2050 Australia
Oh thanks, missed that. I expected the explanation to be near the top under "Description." I may have scanned for the word "sample", which doesn't appear. I could have searched harder. Apologies for the noise. On Tue, Feb 19, 2019 at 5:59 PM S Ellison <S.Ellison at lgcgroup.com> wrote:> > As far as I can tell, the manual help page for ``sd`` > > > > ?sd > > > > does not explicitly mention that the formula for the standard deviation > is > > the so-called "Bessel-corrected" formula (divide by n-1 rather than n). > > See Details, where it says > "Details: > > Like 'var' this uses denominator n - 1. > " > > > > ******************************************************************* > This email and any attachments are confidential. Any u...{{dropped:12}}