tag:blogger.com,1999:blog-19303585.post720825473442867034..comments2020-01-14T07:15:18.661+00:00Comments on John Graham-Cumming: Apple's amusingly round reuse figuresUnknownnoreply@blogger.comBlogger14125tag:blogger.com,1999:blog-19303585.post-81923608870622205392016-04-18T00:59:53.092+00:002016-04-18T00:59:53.092+00:00The logistics company who operates this waste woul...The logistics company who operates this waste would have supplied these figures, there's no conspiracy at work here.Aaron Lavershttps://www.blogger.com/profile/17816475893246633065noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-78172666115793192172016-04-17T13:31:38.023+00:002016-04-17T13:31:38.023+00:00This comment has been removed by the author.Khalil Kacemhttps://www.blogger.com/profile/09754462618623131497noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-26508897962664326432016-04-17T13:17:59.587+00:002016-04-17T13:17:59.587+00:00@Khalil: please email me your address and I'll...@Khalil: please email me your address and I'll send the book.John Graham-Cumminghttps://www.blogger.com/profile/12998100764952319513noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-25870406145062257612016-04-17T13:08:37.150+00:002016-04-17T13:08:37.150+00:00This comment has been removed by the author.Khalil Kacemhttps://www.blogger.com/profile/09754462618623131497noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-43060750365096780352016-04-17T13:08:12.396+00:002016-04-17T13:08:12.396+00:00They simply rounded the weights in pounds to next ...They simply rounded the weights in pounds to next hundred which resulted in the extra 644lbs.<br /><br />Python code:<br /><br /><br />import math<br />def roundup(x):<br /> return int(math.ceil(x / 100.0)) * 100<br /><br /><br />materials_in_kgs = [12750000,6090000,5420000,2050000,1340000,86000,18000,20000,59000,2000,3000,1000]<br /><br />materials_in_lbs = [i*2.204 for i in materials_in_kgs]<br /><br />materials_in_lbs_rounded = [roundup(i) for i in materials_in_lbs]<br /><br />print sum(materials_in_lbs_rounded)Khalil Kacemhttps://www.blogger.com/profile/09754462618623131497noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-80354566625774540652016-04-17T13:04:27.032+00:002016-04-17T13:04:27.032+00:00I suggest it's the rounded totals of various o...I suggest it's the rounded totals of various other precious elements.<br />For example, there's no mention of Indium which is supposedly rare and expensive, so we'd have to assume they did recover it. http://link.springer.com/article/10.1007%2Fs11661-009-9786-4#/page-1 gives a method for recovery and a figure of 6.2mg indium/phone.<br />http://money.cnn.com/2011/10/13/technology/iphone_trade_in/ gives a figure of 34mg of gold/phone; so taking the 2204lbs of gold as the start,<br /><br /> 6.2*2204<br /> -------- = 402lb<br /> 34<br /><br />(Or 1000kg->182kg which you round to 200kg and call 440lb)<br /><br />My bet is that the Indium end up rounded to 300kg which ends up as 661kg which gets to within the rounding to 100lb that your total has.Davehttps://www.blogger.com/profile/06367977607950996348noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-11179437725652907722016-04-17T13:04:14.196+00:002016-04-17T13:04:14.196+00:00I don't know. The closest I can get if by summ...I don't know. The closest I can get if by summing ceil(pounds / 1000, 1 sf), which gets me to 61.357.700.Luchttps://www.blogger.com/profile/17726930447371750605noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-1244160305680296262016-04-17T12:47:47.925+00:002016-04-17T12:47:47.925+00:00My guess: one or a few of the metric figures had m...My guess: one or a few of the metric figures had more degrees of precision, and the total incorporated those numbers and then rounded, instead of just adding up the rounded ones. I've seen this in scientific calculations.Aren Cambrehttps://www.blogger.com/profile/13044481831467661196noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-1604049549914968222016-04-17T12:33:43.429+00:002016-04-17T12:33:43.429+00:00Maybe they threw in the scraps from the manufactur...Maybe they threw in the scraps from the manufacturing process. They realized they actually had a little more on hand that was "salvageable" and over 600 lb moves the needle enough to be worth adding to the number?JMarthttps://www.blogger.com/profile/03338738247704201174noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-68186169580333144212016-04-17T12:22:16.506+00:002016-04-17T12:22:16.506+00:00This comment has been removed by the author.Support for Rosehttps://www.blogger.com/profile/00042618791125358171noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-82412338321822229632016-04-17T12:11:19.733+00:002016-04-17T12:11:19.733+00:00I can suggest an answer for the remaining 644lbs: ...I can suggest an answer for the remaining 644lbs: <b>rounding errors</b><br /><br />Here's my hypothesis:<br /><br />1. The figures were measured with reasonable accuracy on a per-material basis.<br />2. The per-material measurements were taken in kg. That's an ISO standard unit, and the initiatives are global after all.<br />3. The accurate measurements for 12 materials were then summed to produce the grand total that was probably a bit less than 27,839,000kg.<br />4. Next, all the figures were rounded to the nearest 1,000kg. Because hey, iProducts have round edges. <br />5. Some precision was lost in the process for each measurement. Across a large set, we can expect the errors to average out – but here our set is only N=12, so not huge. So, more of the numbers were reduced than increased; but the grand total number happened to be increased in the rounding.<br /><br /><b>Sanity check:</b> the discrepancy is about 292kg, or ~25kg for each measurement. That's a couple of orders of magnitude lower than the rounding margin (nearest 1000).<br /><br />T<br />Lex Lexicalhttps://www.blogger.com/profile/13848392465019647675noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-63630089344723515042016-04-17T12:11:16.422+00:002016-04-17T12:11:16.422+00:00"911 Metallurgist, which helps mines and recy..."911 Metallurgist, which helps mines and recyclers extract precious metals from ore and, apparently, phones, has exhaustively checked the iPhones and other mobile devices. Each iPhone 5, for instance, contains $1.58 of gold, $.36 of silver, $.05 of platinum, and $.12 of copper."<br /><br />So I'll say the missing item is platinum.tacoshttps://www.blogger.com/profile/08099204076640163905noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-73099516794504095062016-04-17T12:04:10.764+00:002016-04-17T12:04:10.764+00:00They used more precise conversion for calculations...They used more precise conversion for calculations and then rounded it to 1lbs for display.Piotrek R.https://www.blogger.com/profile/06462321801265908638noreply@blogger.comtag:blogger.com,1999:blog-19303585.post-24090798665531851122016-04-17T11:55:39.891+00:002016-04-17T11:55:39.891+00:00This comment has been removed by the author.Mark Lhttps://www.blogger.com/profile/11477290626756045094noreply@blogger.com