The only reference that I can think of (a bit subtle/indirect) is: http://www.burns-stat.com/pages/Tutor/spreadsheet_addiction.html (look in the section on Propagation of Blanks).
But I think that it really comes down to the following 2 variations on a rule: 1. Important decisions (such as throwing away information) should be made by a human not a computer 2. Important decisions (such as throwing away information) should be made by a person familiar with the data and scientific question, not by a programmer separated in time and space from the real question who was unlikely to be able to anticipate every situation. -- Gregory (Greg) L. Snow Ph.D. Statistical Data 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 Adam D. I. Kramer > Sent: Tuesday, March 24, 2009 12:24 PM > To: r-help@r-project.org > Subject: [R] Why na.rm=FALSE is the default > > Dear Colleagues, > > I've been searching for a post or article or something which > explains why having na.rm=FALSE or na.action=na.fail as the default is > a > better choice than TRUE or na.omit. > > I understand the basic argument: it does not make sense to > average a > nonexistance into an aggregate, and removing them implicitly leads to > accidental pairwise deletion in some cases, and sum(x) / length(x) < > mean(x) > (which many would find disturbing)...I'm just looking for a source to > cite > on this issue to support mimicking R's behavior in a database system's > aggregating functions (sum, avg, var, etc.). > > Cordially, > Adam Kramer > Ph.D. Candidate, Social Psychology > University of Oregon > adik at uoregon dot edu > > ______________________________________________ > R-help@r-project.org 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. ______________________________________________ R-help@r-project.org 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.
