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Index of Subjects --001a11c24d2092eb4304e1026952 Content-Type: text/plain; charset=ISO-8859-1 I was waiting for an informed reply. What Ian is pointing out, gently, is that each of us is too hung up about the precise accuracy of our own data. But in the big picture, as actually used by someone else, our single data points are one of hundreds or thousands. Any bias we have individually is balanced by someone else who differs in the opposite direction. Therefore, a "25" or a "35" is vastly more informative than an "X". If we all make a sincere effort, an actual figure is best & there is no need to lose sleep over them. As an aside, I do use "X" when I'm doing my favourite walks & have no intention of counting ravens, crows, gulls, song sparrows etc. for the 20th time this year. But I will have counted Song Sparrows, for example, several times during the peak singing season and will have close to an accurate count of (primarily) singing males on record. Regards, Rick Whitman On Mon, Jul 8, 2013 at 12:12 PM, <iamclar@dal.ca> wrote: > All: > > Nancy's dilemma and suggestions on estimating numbers for eBird are > important. I have been a frequent user of eBird, atlas, CBC, BBS, etc., > over the years in estimating trends and patterns,. I believe the dictum of > a statistician colleague that "a large number of bad numbers (as long as > not biassed) are as good as a small number of good numbers" (a recasting of > the "law of large numbers"). Even the casual reporting of numbers like > "lots" or "common" on naturens are less useful for section editors of "NS > Birds" than are estimates. > > Nancy suggests that a range of categories could be available on eBird > 2-10, 11-50, etc., but the "users" of these numbers would still have to > turn these into a single number for trend analyses, etc. I believe that an > educated guess is better; Why not just take the rough number between 11 and > 50, e,g., that you think might be better - 20 or 40? > > Another possible guide might be that used during the first (1980s) NS > Atlassers of entering log categories 1-10, 10-100, etc. (natural logs even > better). Then (as was done) the user (or indeed the observer) can use the > geometric mean (about 3, about 30, etc.). > > Cheers, Ian > > Ian McLaren > --001a11c24d2092eb4304e1026952 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable <div dir=3D"ltr">I was waiting for an informed reply. What Ian is pointing = out, gently, is that each of us is too hung up about the precise accuracy o= f our own data. But in the big picture, as actually used by someone else, o= ur single data points are one of hundreds or thousands. Any bias we have in= dividually is balanced by someone else who differs in the opposite directio= n.<div> <br></div><div style>Therefore, a "25" or a "35" is vas= tly more informative than an "X". If we all make a sincere effort= , an actual figure is best & there is no need to lose sleep over them.<= /div> <div style><br></div><div style>As an aside, I do use "X" when I&= #39;m doing my favourite walks & have no intention of counting ravens, = crows, gulls, song sparrows etc. for the 20th time this year. But I will ha= ve counted Song Sparrows, for example, several times during the peak singin= g season and will have close to an accurate count of (primarily) singing ma= les on record.</div> <div style><br></div><div style>Regards,</div><div style>Rick Whitman</div>= <div class=3D"gmail_extra"><br><br><div class=3D"gmail_quote">On Mon, Jul 8= , 2013 at 12:12 PM, <span dir=3D"ltr"><<a href=3D"mailto:iamclar@dal.ca= " target=3D"_blank">iamclar@dal.ca</a>></span> wrote:<br> <blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p= x #ccc solid;padding-left:1ex">All:<br> <br> Nancy's dilemma and suggestions on estimating numbers for eBird are imp= ortant. I have been a frequent user of eBird, atlas, CBC, BBS, etc., over t= he years in estimating trends and patterns,. I believe the dictum of a stat= istician colleague that "a large number of bad numbers (as long as not= biassed) are as good as a small number of good numbers" (a recasting = of the "law of large numbers"). Even the casual reporting of numb= ers like "lots" or "common" on naturens are less useful= for section editors of "NS Birds" than are estimates.<br> <br> Nancy suggests that a range of categories could be available on eBird 2-10,= 11-50, etc., but the "users" of these numbers would still have t= o turn these into a single number for trend analyses, etc. I believe that a= n educated guess is better; Why not just take the rough number between 11 a= nd 50, e,g., that you think might be better - 20 or 40?<br> <br> Another possible guide might be that used during the first (1980s) NS Atlas= sers of entering log categories 1-10, 10-100, etc. (natural logs even bette= r). Then (as was done) the user (or indeed the observer) can use the geomet= ric mean (about 3, about 30, etc.).<br> <br> Cheers, Ian<br> <br> Ian McLaren<br></blockquote></div> </div></div> --001a11c24d2092eb4304e1026952--
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