The perpetual calendar
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From: Robert Bannister on 22 Feb 2010 20:37 Brian M. Scott wrote: > R H Draney wrote: > > [...] > >> If you want a crank, find the person who came up with >> Daylight Saving Time.... > >> Then find his successor who decided that DST should apply >> for more of the year than "Standard" time....r > > I like DST; my only objection is that we don't have it all > year round. > > Brian I think you should go and live in Inverness until you change your mind. -- Rob Bannister
From: Robert Bannister on 22 Feb 2010 20:38 Ant�nio Marques wrote: > Brian M. Scott wrote (22-02-2010 21:33): >> R H Draney wrote: >> >> [...] >> >>> If you want a crank, find the person who came up with Daylight Saving >>> Time.... >> >>> Then find his successor who decided that DST should apply for more of >>> the year than "Standard" time....r >> >> I like DST; my only objection is that we don't have it all year round. > > Yeah, what sense does it make to save daylight only during half of the > year. What I want to know is what do they do with all this daylight they've saved? I'm not getting it, and I think they're using my daylight for nefarious activities. -- Rob Bannister
From: Andrew Usher on 22 Feb 2010 21:02 Transfer Principle wrote: > Compared to some calendar reformer's proposal's, Usher's is > relatively tame. He only proposes a new leap year rule and new > dates for the Christian holidays, as opposed to more radical > proposals (such as the 13-month calendar proposal mentioned > later in this thread). I see you've worked out yourself many of the implications I hinted at in the original post and elsewhere. It's quite remarkable to me that this all works! > Travelers are often forced to > leave several days before Christmas because the airlines are > booked on the days closer to the holiday. In years in which > Christmas is mid-week, the workers are likely to take those > extra days off anyway, but when Christmas is on a Sunday as > per Usher's proposal, workers don't necessarily wait until > Friday, December 23rd at 5PM to begin their holiday travel. So > workers may be as likely to take off extra days under Usher's > proposal as they are under the current Gregorian calendar. I think this is a valid point, but still it's clear that workers would be less likely to take days off. Not everyone travels a great distance for Christmas, nor is everyone allowed to take that many days off. > (Also, Sunday Christmases often cause headaches for school > calendar planners as well. Some schools actually have school > all the way up until Friday, December 23rd, and then have low > attendance rates the last few days. Schools could end on the Thursday or Wednesday, then. > One could have school end > a full week before Christmas instead, but then the standard > two-week winter break might end too close to New Year's Day, > or even before, since a December 21st Usher Christmas would > result in school resuming on Monday, December 29th, which is > before New Year's Day.) Many schools have a winter break not fixed in length already; they resume on the weekday after New Year's and they still could. I would rather, though, extend the break to the end of a full week. > > 3. That the leap year rule be changed to have a leap year occur every > > fourth save that it be delayed when the leap year would start on a > > Thursday, and that this gives 7 leap years in every 29, which is near > > enough. > > There's a huge problem with the Usher leap year plan here. I > can see why Usher would want to avoid leap years starting on > Thursdays, since Easter, being 15 weeks after Christmas, > would fall on April 4th such years, which is outside of the > April 5-11 range given by Usher elsewhere in this thread. Yes, Easter on Apr. 4 would throw the whole rest of the year off. Having a rule like this seems not unreasonable; the Jewish calendar has it (and more complicated, too). > But suppose the Usher plan had been implemented in 2004, which > was the last time a leap year started on Thursday. Thus the > Usher leap year would have been 2005 instead. Now let's look > at a table of Usher New Year's Days and leap years: > > 2004: Thursday > 2005: Friday (leap year) > 2006: Sunday > 2007: Monday > 2008: Tuesday > 2009: Wednesday (leap year) > 2010: Friday > 2011: Saturday > 2012: Sunday > 2013: Monday (leap year) > 2014: Wednesday > 2015: Thursday > 2016: Friday > 2017: Saturday (leap year) > 2018: Monday > 2019: Tuesday > 2020: Wednesday > 2021: Thursday (common year) > 2022: Friday (leap year) > 2023: Sunday > > And now we see the problem. The resulting leap year cycle > isn't 7 leap years in 29 years, but rather 4 leap years in > only 17 years. This is because by skipping Thursday leap > years, Usher unwittingly skipped Tuesday and Sunday leap > years as well! And so the resulting mean year length is > only 365+4/17 = 365.2352941 days, which is less accurate > than the Gregorian leap year rule. Yes, this was an error I found shortly after posting it. Doh. One needs, to correct this, to sometimes have a shorter than 4-year interval between leap years. This can be accomplished by inserting at intervals, a shorter cycle as follows (using your notation): Year 1: Friday (leap year) Year 2: Sunday Year 3: Monday Year 4: Tuesday (leap year) Year 5: Thursday Year 6: Friday (leap year) 7 17-year cycles and 1 of these make 30 leap years in 124, or a year of 365+30/124 = 365.2419 days. > Notice that the current USA Labor Day (first Monday in > September) already occurs exactly 11 weeks and three days > before Usher Thanksgiving. As Usher points out later, this > is convenient for college football, which traditionally began > on Labor Day weekend and ended on Thanksgiving, with enough > time to play 11 games in between. (The recent practice of > playing 12 games instead of 11 occurred because in a recent > year when Labor Day and Thanksgiving were 12 weeks and three > days apart, colleges scheduled an extra game, then kept on > scheduling 12 games even when the period between the two > holidays switched back to 11 weeks and three days.) My college football season would always have 13 weekends (rather than 13 or 14); whether 11 or 12 games is allowed is not my concern. > Also, the current USA Memorial Day (last Monday in May) > already occurs exactly seven weeks and one day after the > Usher Easter. In other words, it's always Whit Monday. (For > those who are tired of all these USA holiday references, > note that the UK Spring Bank Holiday occurs on the same day > as USA Memorial Day, while the UK Summer Bank Holiday occurs > exactly one week before USA Labor Day.) Indeed, and I had those in mind as well. Andrew Usher
From: Evan Kirshenbaum on 22 Feb 2010 21:24 Andrew Usher <k_over_hbarc(a)yahoo.com> writes: > Evan Kirshenbaum wrote: > >> > mine, yours, his, hers, its,ours, theirs. >> > >> > Not one possessive pronoun has an apostrophe. >> >> One should be sure of one's facts before making such assertions. >> (Or should that be "ones"?) > > 'One' is not, grammatically, a pronoun. It is a nominalised > adjective (the number one) that is used in place of a pronoun. Both Merriam-Webster and the OED appear to disagree with you. -- Evan Kirshenbaum +------------------------------------ HP Laboratories |You gotta know when to code, 1501 Page Mill Road, 1U, MS 1141 | Know when to log out, Palo Alto, CA 94304 |Know when to single step, | Know when you're through. kirshenbaum(a)hpl.hp.com |You don't write your program (650)857-7572 | When you're sittin' at the term'nal. |There'll be time enough for writin' http://www.kirshenbaum.net/ | When you're in the queue.
From: R H Draney on 22 Feb 2010 21:58
Michael Stemper filted: > >mine, yours, his, hers, its,ours, theirs. > >Not one possessive pronoun has an apostrophe. That might just be somebody's opinion....r -- "Oy! A cat made of lead cannot fly." - Mark Brader declaims a basic scientific principle |