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Index of Subjects --Apple-Mail-15-51593885 Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed Hi Dave, It looks to me as if your scale is biased against odd numbers. In the numbers represented, 80 are even numbers and only 11 are odd numbers, a significant departure from the ~ 50:50 ratio one would expect. Cheers, Chris On 3-Dec-06, at 5:19 PM, David & Alison Webster wrote: > Dear All, Dec 3, 2006 > There is, as usual, a lull in NatureNS traffic as we near winter > and this lull provides an opportunity to comment on something that > I found interesting; a digital readout with 'missing numbers'. > I have weighed myself on digital bathroom scales, that have > readout to the nearest pound, for about 255 sundays and readout > spans 192 to 168 lb. It soon became clear that some weights were > favoured relative to others. For example for the 91 weights on one > page (May 4, 2003 to Jan 23, 2004), the readings cover a range of > 172 to 185 but some intermediate weights were not represented. > > The number of readings at each weight within this range were: > 172; 7 > 173; 0 > 174; 6 > 175; 3 > 176; 9 > 177; 0 > 178; 15 > 179; 7 > 180; 20 > 181; 0 > 182; 15 > 183; 0 > 184; 8 > 185; 1 > indicating that some weights, such as 177, 181, and 183 are > likely to be filtered out by some distortion in the instrument and > appear as some different reading. > > Much of the world uses metric so I looked at the implications > of a kilograms to pounds retrofit that was tacked onto scales that > had been designed to read to the nearest kilogram. For one > artificial case, with input being a series of weights difffering by > 0.05 kg (76.50, 76.55...); assuming output rounded to nearest > kilogram, then converted to lb by dividing by 0.45 and then rounded > to the nearest pound, the frequency of weights is either zero or > 20 within the range 171 to 187-- > > Weights with a frequency of 20 were 171, 173, 176, 178, 180, 182, > 184 & 187 while > weights with a frequency of zero were 172, 174, 175, 177, 179, 181, > 183, 185 & 186. > > The gaps in the artificial readouts don't exactly match gaps in > the actual readout (177, 181 and 183 do but not 179) but both > examples show that a rock-solid digital readout to zero or more > decimal places may not be as reliable as it appears. > > Yours truly, Dave Webster, Kentville > > > > _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._. Christopher Majka Email: <c.majka@ns.sympatico.ca> Halifax, Nova Scotia, Canada chebucto.ca/~aa051/Profile.html "I have discovered the art of deceiving diplomats. I speak the truth and they never believe me." - Camillo di Cavour _._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._._. --Apple-Mail-15-51593885 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=ISO-8859-1 <HTML><BODY style=3D"word-wrap: break-word; -khtml-nbsp-mode: space; = -khtml-line-break: after-white-space; ">Hi Dave,=A0<DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>It looks to me as if your = scale is biased against odd numbers. In the numbers represented, 80 are = even numbers and only 11 are odd numbers, a=A0significant departure from = the ~ 50:50 ratio one would expect.</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Cheers,</DIV><DIV><BR = class=3D"khtml-block-placeholder"></DIV><DIV>Chris</DIV><DIV><BR><DIV><DIV= >On 3-Dec-06, at 5:19 PM, David & Alison Webster wrote:</DIV><BR = class=3D"Apple-interchange-newline"><BLOCKQUOTE type=3D"cite"><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; ">Dear All,<SPAN class=3D"Apple-converted-space">=A0 =A0= =A0 =A0 =A0 =A0 </SPAN>Dec 3, 2006</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN = class=3D"Apple-converted-space">=A0=A0 </SPAN>There is, as usual, a lull = in NatureNS traffic as we near winter and this lull provides an = opportunity to comment on something that I found interesting; a digital = readout with 'missing numbers'.</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN = class=3D"Apple-converted-space">=A0=A0 =A0 </SPAN>I have weighed myself = on digital bathroom scales, that have readout to the nearest pound, for = about 255 sundays and readout spans 192 to 168 lb. It soon became clear = that some weights were favoured relative to others. For example for the = 91 weights on one page (May 4, 2003 to Jan 23, 2004), the readings cover = a range of 172 to 185<SPAN class=3D"Apple-converted-space">=A0 = </SPAN>but some intermediate weights were not represented.</DIV><DIV = style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: 0px; = margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style=3D"margin-top: = 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; "><SPAN = class=3D"Apple-converted-space">=A0=A0 </SPAN>The number of readings at = each weight within this range were:</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">172; = 7</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: = 0px; margin-left: 0px; ">173; 0</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">174; = 6</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: = 0px; margin-left: 0px; ">175; 3</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">176; = 9</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: = 0px; margin-left: 0px; ">177; 0</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">178; = 15</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: = 0px; margin-left: 0px; ">179; 7</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">180; = 20</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: = 0px; margin-left: 0px; ">181; 0</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">182; = 15</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px; margin-bottom: = 0px; margin-left: 0px; ">183; 0</DIV><DIV style=3D"margin-top: 0px; = margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">184; = 8</DIV><DIV style=3D"margin-top: 0px; margin-right: 0px