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RE: Some modifications of China related timezone info.
by Andy Lipscomb April 28, 2006

April 28, 2006

One other issue that may or may not be worth considering. Beijing mean time was, prior to the introduction of time zones, the standard for determining midnight in the computation of the Chinese calendar. Thus, having an entry with Beijing's mean time and transition point may be a help to programmers seeking to implement that calendar.

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Re: Some modifications of China related timezone info.
by Zhe Su April 28, 2006

April 28, 2006

Hi, So counting both kind of population, as Beijing and Shanghai have almost same amount of population (though Shanghai has slightly more population right now), and as Beijing is capital of China. I just suggest to add Asia/Beijing into timezone database along with Asia/Shanghai. Just like what was done in my proposed patch. Regards James Su On 4/28/06, Ken Pizzini <tz.(a)explicate.org> wrote: > On Fri, Apr 28, 2006 at 03:52:53PM +0800, Zhe Su wrote: > > I don't think we should count floating population, because those > > part of population is "floating", many of them will move around > > frequently. > > While _individuals_ in this category may come and go, in the aggregate > the "floating" population in these areas has been consistently and > continually growing. They are a real population. > The statistics I've seen (at least the ones that were of good > quality) only reported the *officially registered* portion of these > populations, so clearly the actual population of each urban > agglomeration is actually higher than typically reported, but I'm not > sure how this might affect the relative populations of Beijing and > Shanghai. > > > And the data source that you mentioned is apparently wrong. > > It's not that simple. The data sources I've been able to track down > are all over the map as to the absolute number associated with each > city. Part of this is just that they are reporting based on different > criteria: is the registered transient population included? > Is the unregistered transient population estimated? Is the census > just of the city proper, or does it include the entirety of the "urban > agglomeration"? How recently did the enumeration take place? > And what methodology was used to collect the information (official > census vs. statistical sampling, for example)? > > Except for the fact that it is five years out of date in a region of > very high demographic flux, the document that I would have trusted > most is the Fifth National Census (done in 2000-2001), which still > rated Shanghai more populous by a significant amount. > But clearly that isn't sufficient, so let's compare the value that you > quoted from a Dec. 2005 page on www.bj.xinhuanet.com with a page I > found from Jan. 2005 (in English): > > http://www.chinadaily.com.cn/english/doc/2005-01/10/content_407463.htm > If the two sets of values are presumed to both be correct, then that > means that Beijing's population grew by an astounding 10% over the > course of the year! (Almost all from immigration, since you also > quoted the 0.07% "natural" growth rate.) Surely there must be a > disagreement between how the National Population and Family Commission > of China (quoted by xinhuanet) and the Beijing Municipal Public > Security Bureau (quoted by chinadaily) do their counting. > This is the very kind of discrepancy that makes determining "the" > truth very challenging. > > > > So I suggest the following: the populations do seem to have converged > significantly over the 15 or so years since the Asia/Shanghai entry > was created, and the trend lines strongly suggest that if Beijing has > not yet overtaken Shanghai as the largest city in China, it is very > likely to do so soon. So I say that Asia/Beijing and Asia/Shanghai > should just be preemptively linked: we're talking concentrations of > over 15 million souls in each case anyway, which is surely significant > enough to be worth at least as much as the Africa/Timbuktu link? (As > to which is listed as primary and which as the link, I really don't > care. Toss a coin.) > > --Ken Pizzini >

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Re: Some modifications of China related timezone info.
by Ken Pizzini April 28, 2006

April 28, 2006

On Fri, Apr 28, 2006 at 03:52:53PM +0800, Zhe Su wrote: > I don't think we should count floating population, because those > part of population is "floating", many of them will move around > frequently. While _individuals_ in this category may come and go, in the aggregate the "floating" population in these areas has been consistently and continually growing. They are a real population. The statistics I've seen (at least the ones that were of good quality) only reported the *officially registered* portion of these populations, so clearly the actual population of each urban agglomeration is actually higher than typically reported, but I'm not sure how this might affect the relative populations of Beijing and Shanghai. > And the data source that you mentioned is apparently wrong. It's not that simple. The data sources I've been able to track down are all over the map as to the absolute number associated with each city. Part of this is just that they are reporting based on different criteria: is the registered transient population included? Is the unregistered transient population estimated? Is the census just of the city proper, or does it include the entirety of the "urban agglomeration"? How recently did the enumeration take place? And what methodology was used to collect the information (official census vs. statistical sampling, for example)? Except for the fact that it is five years out of date in a region of very high demographic flux, the document that I would have trusted most is the Fifth National Census (done in 2000-2001), which still rated Shanghai more populous by a significant amount. But clearly that isn't sufficient, so let's compare the value that you quoted from a Dec. 2005 page on www.bj.xinhuanet.com with a page I found from Jan. 2005 (in English): http://www.chinadaily.com.cn/english/doc/2005-01/10/content_407463.htm If the two sets of values are presumed to both be correct, then that means that Beijing's population grew by an astounding 10% over the course of the year! (Almost all from immigration, since you also quoted the 0.07% "natural" growth rate.) Surely there must be a disagreement between how the National Population and Family Commission of China (quoted by xinhuanet) and the Beijing Municipal Public Security Bureau (quoted by chinadaily) do their counting. This is the very kind of discrepancy that makes determining "the" truth very challenging. So I suggest the following: the populations do seem to have converged significantly over the 15 or so years since the Asia/Shanghai entry was created, and the trend lines strongly suggest that if Beijing has not yet overtaken Shanghai as the largest city in China, it is very likely to do so soon. So I say that Asia/Beijing and Asia/Shanghai should just be preemptively linked: we're talking concentrations of over 15 million souls in each case anyway, which is surely significant enough to be worth at least as much as the Africa/Timbuktu link? (As to which is listed as primary and which as the link, I really don't care. Toss a coin.) --Ken Pizzini

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Re: Some modifications of China related timezone info.
by Zhe Su April 28, 2006

April 28, 2006

Hi, I don't think we should count floating population, because those part of population is "floating", many of them will move around frequently. And the data source that you mentioned is apparently wrong. Regards James Su On 4/28/06, Paul Eggert <eggert(a)cs.ucla.edu> wrote: > Robert Elz <kre(a)munnari.oz.au> writes: > > > Having a simple rule that always gets followed allows us to ignore > > endless arguments > > Yes, that's one of the principal motivations. > > > Of course, if it is a close thing, and it is possible that Shanghai > > may overtake Beijing again next year (or something) then keeping > > switching backwards and forwards would be irrational > > Yes, in the past when this has happened, we've tried to avoid change > for the sake of tracking the current ephemeral champion. Of course > this has to be done within reason; if the new champion is undisputed > then it would be time to change. > > But as far as Beijing vs Shanghai goes, it seems that the current > headcount leader is still Shanghai, if we include the floating > population and use the statistics James Su mentioned. > > Also, if we count the entire metropolitan-area population, the > statistics I've seen suggest that Beijing still trails well behind > Shanghai. See <http://www.citypopulation.de/World.html>, for example, > which gives 12.1 million for Beijing and 18.2 million for Shanghai. > Or > <http://www.world-gazetteer.com/wg.php?men=gcis&dat=32&geo=-54&srt=pna > n&col=aohdq&pt=a&srt=pnan>, which gives 11.5 million for Beijing and > 14.9 million for Shanghai. >

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Re: Some modifications of China related timezone info.
by Paul Eggert April 28, 2006

April 28, 2006

Robert Elz <kre(a)munnari.oz.au> writes: > Having a simple rule that always gets followed allows us to ignore > endless arguments Yes, that's one of the principal motivations. > Of course, if it is a close thing, and it is possible that Shanghai > may overtake Beijing again next year (or something) then keeping > switching backwards and forwards would be irrational Yes, in the past when this has happened, we've tried to avoid change for the sake of tracking the current ephemeral champion. Of course this has to be done within reason; if the new champion is undisputed then it would be time to change. But as far as Beijing vs Shanghai goes, it seems that the current headcount leader is still Shanghai, if we include the floating population and use the statistics James Su mentioned. Also, if we count the entire metropolitan-area population, the statistics I've seen suggest that Beijing still trails well behind Shanghai. See <http://www.citypopulation.de/World.html>, for example, which gives 12.1 million for Beijing and 18.2 million for Shanghai. Or <http://www.world-gazetteer.com/wg.php?men=gcis&dat=32&geo=-54&srt=pnan&col=…>, which gives 11.5 million for Beijing and 14.9 million for Shanghai.

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Saskatchewan (2007)
by Chris Walton April 28, 2006

April 28, 2006

Over the past couple of months I have posted a number of e-mails related to Canadian time legislation. I never mentioned Saskatchewan because most of the province does not observe daylight saving time. There are actually two small regions in Saskatchewan that do use daylight saving time: 1)Lloydminster and surrounding area. 2)Creighton and Denare Beach area. Both of these regions are briefly mentioned in TZDATA's "northamerica" file. ################# The city of Lloydminster straddles the Alberta/Saskatchewan border. It uses MST/MDT. There is a special bit of legislation called the "Lloydminster Charter". The bylaws in the charter cover the entire city (both sides of the provincial border). Here are two URLs for the charter. Government of Alberta web site: http://www.qp.gov.ab.ca/Documents/REGS/1979_043.CFM Government of Saskatchewan web site: http://www.qp.gov.sk.ca/documents/english/Statutes/Historical/lloydchr.pdf Section 5(2) reads: ------------------------------------------------------------------ "Whenever any particular time of day is referred to in this Charter, the same shall mean Mountain Standard Time except that in every year during the period between two o'clock in the forenoon of the first Sunday in April and two o'clock in the forenoon of the last Sunday in October it shall mean Central Standard Time." ----------------------------------------------------------------- Since Lloydminster has traditionally followed the daylight savings practices of Alberta, I assume that the charter will have to be updated for 2007. ################# The Battle River region surrounding the city of Lloydminster uses the same time as Lloydminster. Presumably the bylaws in the Lloydminster Charter don't apply outside the city limits. So the region surrounding Lloydminster on the east side of the provincial border is subject to the rules in the Saskatchewan Time Act. The Saskatchewan Time Act defines time for all regions of the province except the city of Lloydminster. The Act allows the rules in western parts of the province to be overridden by public election. http://www.qp.gov.sk.ca/documents/english/statutes/statutes/t14.pdf Several sections of the act are of interest: ---------------------------------------------------------------- 2(i) "summer period means that period in each year beginning at two o'clock, mountain standard time, in the forenoon of the first Sunday in April and ending at two o'clock, mountain standard time, in the forenoon of the last Sunday in October;" --------------------------------------------------------------- "Non-application of Act 5 Nothing in this Act applies to a reference to time in: (a) The Lloydminster Charter; or"... --------------------------------------------------------------- "Time in certain areas of western Saskatchewan 8(1) The time to be used and observed in western Saskatchewan: (a) during the summer period, is central standard time; and (b) during the winter period, is mountain standard time, except in respect of any time option area where central standard time is decided upon by a majority of the electors of the time option area voting with respect thereto under this Act whose ballots are not rejected. (2) Notwithstanding subsection (1), on and from the commencement of the winter period in 1983 and until a vote is taken in accordance with this Act, the time to be used and observed: (a) in the Battle River Time Option Area: (i) during the summer period, is central standard time; and (ii) during the winter period, is mountain standard time; and (b) throughout the year in the Paynton Time Option Area is central standard time." --------------------------------------------------------------------- Notice that the transition from daylight time to standard time is supposed to take place at 2:00am MST (3:00MDT). This is one hour after the transition defined in the Lloydminster charter. Therefore, the area surrounding Lloydminster on the east side of the provincial border should be out of sync with Lloydminster for one hour each year. Ugh! Doesn't this call for a new time zone for a region that probably has no more than 2 or 3 thousand residents. Maybe we just have to ignore the Time Act. The NRC seems to have ignored it. The INMS-NRC site says: "Areas around Lloydminster are in the Mountain Time zone and change at 2:00a.m. local time as in Alberta" http://inms-ienm.nrc-cnrc.gc.ca/en/faq_time_e.php#5 ################ And finally there is the small area that contains the towns of Creighton and Denare Beach. This region uses CST/CDT to align with the city of Flin Flon Manitoba. The use of daylight saving time in this region is in defiance of the Saskatchewan Time Act. Should we stop and ponder what time Creighton and Denare Beach have historically done the transition from daylight time to standard time? Is it: a) 2:00am wall time as is tradition in most parts of the country or b) 02:00 CST (3:00am wall time) as per the old Manitoba Time Act or c) 02:00 MST (4:00am wall time) as per the definition of "summer time" in the Saskatchewan Time Act? or d) 8:07am wall time because we can't expect non-law-abiding citizens get up in the middle of the night to change the clocks. It will be interesting to see if the Saskatchewan government bothers to update the Time Act to reflect the extra four weeks of daylight savings in 2007. Personally I think that the all fourteen pages of the old act should be burned and replaced with something more concise. But that is just my opinion. I will keep an eye out for new legislation and I will post an e-mail to this group if I see anything. -chris

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Re: Wisconsin's variation of CDT
by Paul Eggert April 28, 2006

April 28, 2006

Robert Elz <kre(a)munnari.oz.au> writes: > Do you really believe that almost anyone (members of this list perhaps > excepted) actually changes their clock at the precise instant that DST > (or summer time, or whatever it gets called in different areas) > actually changes. Yes, I do. Many people in this country no longer use watches; they use cell phones to tell time. And cell phones did change at 02:00 in Wisconsin on April 2; see <http://www.wisbusiness.com/index.iml?Article=58272>. I myself prefer an old-fashioned pocket watch, but I've observed that my students, whose ages are typically around 20, use cell phones or laptops to tell time just as often as they use watches -- perhaps even more so. Sales of cheap watches reportedly declined 10% last year in the US, most likely due to the popularity of telling time by cell phone; see <http://www.news-journalonline.com/NewsJournalOnline/News/Headlines/frtHEAD0…>. I imagine that people who have to log times (nurses, doctors, police officers, and fire departments, for example) make sure their clocks are close to the consensus time. These days no doubt a lot of this is automated (mostly by our work, by Microsoft's, and by the cell phone companies') but that still counts. I did consult some sources in Wisconsin for what people actually do, and they agreed that 02:00 was the time people switched. See, for example, Bob Petrie, Locals prepare to lose sleep, gain daylight, Sheboygan Press (2006-04-01) <http://www.htrnews.com/apps/pbcs.dll/article?AID=/20060401/SHE0101/60401050…> > More likely to be relevant would be what time the radio stations > announce during the "different" hour I'd be surprised if radio-station time announcements in Wisconsin differed materially from the federal daylight-saving rules.

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Re: Some modifications of China related timezone info.
by Zhe Su April 28, 2006

April 28, 2006

Hi, As I mentioned, according to the data of 2005, the resident population of Beijing is about 13.8 million, Shanghai is about 13.4 million. The natural growth rate of Beijing resident population is about 0.1% (2005 is 0.07%), (data from http://www.bj.xinhuanet.com/bjpd_sdzx/2005-12/06/content_5751145.htm) While, the natural growth rate of Shanghai resident population is -0.03% (2005) and has been kept nagative for 8 years. (data from http://www.happyhome.net.cn/read.asp?subjectid=212&infoid=1452&forumid=14117) Though, the growth rate of floating population of both cities are very high. More and more people come to Beijing and Shanghai from other provinces for work. Regards James Su On 4/28/06, Robert Elz <kre(a)munnari.oz.au> wrote: > Date: Fri, 28 Apr 2006 13:02:16 +0800 > From: "Zhe Su" <james.su(a)gmail.com> > Message-ID: > <278a3d0604272202t58aa5802nf0b11c63bfe110bb(a)mail.gmail.com> > > | Following this rule, "Asia/Beijing" should be used instead of > | "Asia/Shanghai", because more people prefer "Asia/Beijing" in China, > | as Beijing has more people than Shanghai :-) > > If the population of Beijing is greater than that of Shanghai then > you're right, the zone name should be changed (with the old one left > as an alias for a while for people who are used to it). It would > not be the first time that names have changed for this reason (when > relative populations of different cities alters). > > Of course, if it is a close thing, and it is possible that Shanghai > may overtake Beijing again next year (or something) then keeping > switching backwards and forwards would be irrational - so just keeping > things stable should be better, but if (which I would certainly > imagine is possible) that Beijing is simply growing faster than > Shanghai and has now grown bigger, the zone name can change. > > kre >

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Re: Some modifications of China related timezone info.
by Robert Elz April 28, 2006

April 28, 2006

Date: Fri, 28 Apr 2006 13:02:16 +0800 From: "Zhe Su" <james.su(a)gmail.com> Message-ID: <278a3d0604272202t58aa5802nf0b11c63bfe110bb(a)mail.gmail.com> | Following this rule, "Asia/Beijing" should be used instead of | "Asia/Shanghai", because more people prefer "Asia/Beijing" in China, | as Beijing has more people than Shanghai :-) If the population of Beijing is greater than that of Shanghai then you're right, the zone name should be changed (with the old one left as an alias for a while for people who are used to it). It would not be the first time that names have changed for this reason (when relative populations of different cities alters). Of course, if it is a close thing, and it is possible that Shanghai may overtake Beijing again next year (or something) then keeping switching backwards and forwards would be irrational - so just keeping things stable should be better, but if (which I would certainly imagine is possible) that Beijing is simply growing faster than Shanghai and has now grown bigger, the zone name can change. kre

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Re: Some modifications of China related timezone info.
by Zhe Su April 28, 2006

April 28, 2006

Hi, That's not true. According the data from "National Population and Family Commission of China", last year, Shanghai has 13.4 million resident population, while Beijing has 13.8 million resident population. At the same time, Shanghai has about 5.8 floating population, Beijing has about 3 million floating population. So, Beijing has more resident population than Shanghai, though the total population is less. The data from: Shanghai: http://www.chinapop.gov.cn/rkxx/rkxw/t20060406_58076.htm Beijing: http://www.gjjsw.gov.cn/rkzh/zgrk/tjgb/t20040326_2833.htm (Sorry, they are in Chinese) Both for 2005 year. Regards James Su On 4/28/06, David Keegel <djk(a)cybersource.com.au> wrote: > My research on google suggests Beijing is about 15 million population, > and Shanghai is about 18-20 million. > > On Fri, Apr 28, 2006 at 01:02:16PM +0800, Zhe Su wrote: > > Hi, > > Following this rule, "Asia/Beijing" should be used instead of > > "Asia/Shanghai", because more people prefer "Asia/Beijing" in China, > > as Beijing has more people than Shanghai :-) > > > > Regards > > James Su > > -- > ______________________________________________________________________ > _____ David Keegel <djk(a)cybersource.com.au> > http://www.cyber.com.au/users/djk/ > Cybersource P/L: Linux/Unix Systems Administration > Consulting/Contracting >

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