# On which day of the week were you born? **URL:** \ **Category:** In My Humble Opinion\ **Created:** [January 13, 2012, 3:46pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396 "2012-01-13T15:46:07Z")\ **Posts on this page:** 20\ **Page:** 5
**Author:** ![USCDiver](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/uscdiver/32/354_2.png) [@USCDiver](https://boards.straightdope.com/u/USCDiver)\ **Post date:** [January 17, 2012, 7:23am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/81 "2012-01-17T07:23:21Z")
> [@Zeldar](#): > > When you consider that 1/7 = 14.29% it’s not too hard to accept that this “uniform distribution” is just momentarily out of whack, right? Or do we have a truly abnormal occurrence at SDMB? See my notes above, there is prior research and good reasons why this isn’t abnormal. ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [January 17, 2012, 7:38am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/82 "2012-01-17T07:38:06Z")
> [@USCDiver](#): > > See my notes above, there is prior research and good reasons why this isn’t abnormal. Yes. Quite interesting article. No reason to dispute it, but common sense. I seem to recall a similar analysis with a large number of cases considered. As we get more data here, perhaps a stronger case could be made. Right now, I’m appealing to that earlier 44-voter sample as the “norm” to be refuted. ---
**Author:** ![USCDiver](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/uscdiver/32/354_2.png) [@USCDiver](https://boards.straightdope.com/u/USCDiver)\ **Post date:** [January 17, 2012, 8:04am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/83 "2012-01-17T08:04:42Z")
> [@Zeldar](#): > > Yes. Quite interesting article. No reason to dispute it, but common sense. I seem to recall a similar analysis with a large number of cases considered. As we get more data here, perhaps a stronger case could be made. Right now, I’m appealing to that earlier 44-voter sample as the “norm” to be refuted. Well, I’m a physician; my experience and common sense is that it would be unusual for there to be a random distribution for an event that is not at all random. Is there a reason your common sense says different? ---
**Author:** ![Rala](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@Rala](https://boards.straightdope.com/u/Rala)\ **Post date:** [January 17, 2012, 8:14am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/84 "2012-01-17T08:14:11Z")
I accidentally clicked Thursday, but I meant to select Wednesday. ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [January 17, 2012, 8:18am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/85 "2012-01-17T08:18:11Z")
> [@USCDiver](#): > > Well, I’m a physician; my experience and common sense is that it would be unusual for there to be a random distribution for an event that is not at all random. Is there a reason your common sense says different? I suppose it has most to do with the 1/7 ratio being what I would suspect as having more weight than other factors. Beyond elective Cesarean births disrupting the randomness, I have trouble with there being other factors that would make one day more likely than any other for births to occur. If your experience says otherwise, I will yield to a closer observer’s view. But I do anticipate the SDMB population veering closer to a uniform distribution over time. Unless “over time” had already happened. 🙂 Do you have a good explanation for why Saturday and Tuesday are lagging behind, or why Wednesday and Thursday are so far ahead? ---
**Author:** ![BwanaBob](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bwanabob/32/2985_2.png) [@BwanaBob](https://boards.straightdope.com/u/BwanaBob)\ **Post date:** [January 17, 2012, 5:55pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/86 "2012-01-17T17:55:38Z")
Not only a Friday, but Friday at 5:10 pm, which I like to think of as happy hour. ---
**Author:** ![TreacherousCretin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/treacherouscretin/32/476_2.png) [@TreacherousCretin](https://boards.straightdope.com/u/TreacherousCretin)\ **Post date:** [January 17, 2012, 11:14pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/87 "2012-01-17T23:14:10Z")
Friday, the day after Thanksgiving, 1950. . ---
**Author:** ![FatBaldGuy](https://avatars.discourse-cdn.com/v4/letter/f/ecd19e/32.png) [@FatBaldGuy](https://boards.straightdope.com/u/FatBaldGuy)\ **Post date:** [January 18, 2012, 1:33am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/88 "2012-01-18T01:33:04Z")
> [@Gymnopithys](#): > > I’m sure it’s just as consequential as the astrological sign you were born under. We Libras don’t believe in astrology. ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [January 19, 2012, 1:56pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/89 "2012-01-19T13:56:23Z")
Here’s some food for thought and comment, to supplement those who have already expressed opinions about what SDMB’s “day of the week” breakdown will ultimately show. Snapshots from along the way, with the 1/7 (expected value) inserted as a marker between the “above” and “below” groups. Is this a “Uniform Distribution” or something else? Do you know of any studies on the subject beside the ones alluded to or cited above? ```auto On which day of the week were you born? Sunday 7 15.91% Thursday 7 15.91% Friday 7 15.91% 1/7 = 14.29% Monday 6 13.64% Wednesday 6 13.64% Saturday 6 13.64% Tuesday 5 11.36% Voters: 44 Wednesday 36 18.46% Thursday 35 17.95% Friday 30 15.38% Sunday 28 14.36% 1/7 = 14.29% Monday 23 11.79% Tuesday 23 11.79% Saturday 20 10.26% Voters: 195 Wednesday 42 19.53% Thursday 38 17.67% Friday 34 15.81% Sunday 31 14.42% 1/7 = 14.29% Tuesday 26 12.09% Monday 24 11.16% Saturday 20 9.30% Voters: 215 Wednesday 45 18.99% Thursday 43 18.14% Friday 37 15.61% Sunday 35 14.77% 1/7 = 14.29% Monday 27 11.39% Tuesday 26 10.97% Saturday 24 10.13% Voters: 237 Wednesday 47 18.01% Thursday 46 17.62% Friday 43 16.48% 1/7 = 14.29% Sunday 37 14.18% Tuesday 31 11.88% Saturday 29 11.11% Monday 28 10.73% Voters: 261 ``` ---
**Author:** ![Johanna](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johanna/32/8318_2.png) [@Johanna](https://boards.straightdope.com/u/Johanna)\ **Post date:** [January 19, 2012, 2:15pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/90 "2012-01-19T14:15:52Z")
Somehow my day, Monday, dropped from the middle of the stack to the bottom. Well, I’m in the rarest group and that makes me feel special. 😃 Way back when I was born, elective cæsareans were unheard of. When did that become so predominant that it skews this poll? However, my sister’s birth (on a Friday, FTR) at the very end of December 1960 was induced. My dad the CPA jokes it was for the tax deduction. _But somehow I suspect it isn’t actually a joke._ ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [January 19, 2012, 2:54pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/91 "2012-01-19T14:54:03Z")
> [@Johanna](#): > > Somehow my day, Monday, dropped from the middle of the stack to the bottom. Well, I’m in the rarest group and that makes me feel special. 😃 > > Way back when I was born, elective cæsareans were unheard of. When did that become so predominant that it skews this poll? However, my sister’s birth (on a Friday, FTR) at the very end of December 1960 was induced. My dad the CPA jokes it was for the tax deduction. _But somehow I suspect it isn’t actually a joke._ All I can add to your concern over cesareans (and induced) is that my three kids (1964, 1966, and 1969) were all born cesarean and it was not uncommon then. ---
**Author:** ![Sternvogel](https://avatars.discourse-cdn.com/v4/letter/s/bc79bd/32.png) [@Sternvogel](https://boards.straightdope.com/u/Sternvogel)\ **Post date:** [January 19, 2012, 9:43pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/92 "2012-01-19T21:43:47Z")
Sunday, August 30, 1959. Caesarean section. About 10 p.m. ---
**Author:** ![BigT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bigt/32/12044_2.png) [@BigT](https://boards.straightdope.com/u/BigT)\ **Post date:** [January 20, 2012, 3:40pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/93 "2012-01-20T15:40:05Z")
This is one of those things I figured out years ago. Not only do I know that I was born on a Saturday, but my sister, who was born 3 years and 3 days later than me was also born on a Saturday. I was born at 7:36 PM and was two weeks early, and my sister was born at 8:48 PM, and she was 3 days late. Yip, she was supposed to be born on my third birthday. Mom told me she was going to be my birthday present. I believe I cried when she wasn’t born by the next day. And if I had to posit a reason for a non-random distribution, I would wonder about how regular the 40 weeks is, and what days people are more likely to have sex. Monday’s the start of the week for most people, so it’s less likely. But, then again, you’d think being home alone on Saturday would make it more likely, and it’s the second lowest. Yeah, that’s probably bunk. ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [January 20, 2012, 4:07pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/94 "2012-01-20T16:07:54Z")
> [@BigT](#): > > … And if I had to posit a reason for a non-random distribution, I would wonder about how regular the 40 weeks is, and what days people are more likely to have sex. Monday’s the start of the week for most people, so it’s less likely. But, then again, you’d think being home alone on Saturday would make it more likely, and it’s the second lowest. > > Yeah, that’s probably bunk. In addition to the other comments in this thread on previous studies and distributions, I have tried to locate some data from large-scale analysis of this issue. I’ve found all sorts of answers, with Tuesday and Wednesday leading the list. Our survey has varied a little from ```auto Wednesday 36 18.46% Thursday 35 17.95% Friday 30 15.38% Sunday 28 14.36% 1/7 = 14.29% Monday 23 11.79% Tuesday 23 11.79% Saturday 20 10.26% Voters: 195 ``` to the most recent ```auto Wednesday 50 18.18% Thursday 48 17.45% Friday 44 16.00% Sunday 40 14.55% 1/7 = 14.29% Tuesday 33 12.00% Monday 30 10.91% Saturday 30 10.91% Voters: 275 ``` But the “expected value” of 14.29% (1/7) seems to maintain its 4/3 dividing point and the same three days stay low, even if they and the top four do a little juggling around for position. Has anybody seen any Census Bureau data on this issue? Or some other large-scale and reliable source? It looks to me like rolling a 7-sided die several hundred times would give an answer as reasonable as some I’ve seen. 🙂 ---
**Author:** ![Wednesday\_Evening](https://avatars.discourse-cdn.com/v4/letter/w/b2d939/32.png) [@Wednesday\_Evening](https://boards.straightdope.com/u/Wednesday_Evening)\ **Post date:** [January 21, 2012, 12:10am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/95 "2012-01-21T00:10:59Z")
Born on (American) Thanksgiving so…Thursday. My son was born on a Saturday. I can never remember what day my daughter was born on, though. Tuesday? \ Whaddaya know, I was right! Too bad I won’t remember it, though. ---
**Author:** ![Marconi\_N.Cheese](https://avatars.discourse-cdn.com/v4/letter/m/57b2e6/32.png) [@Marconi\_N.Cheese](https://boards.straightdope.com/u/Marconi_N.Cheese)\ **Post date:** [January 21, 2012, 12:27am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/96 "2012-01-21T00:27:18Z")
Wednesday. I don’t know why, but that makes me feel somewhat sad. ---
**Author:** ![USCDiver](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/uscdiver/32/354_2.png) [@USCDiver](https://boards.straightdope.com/u/USCDiver)\ **Post date:** [January 21, 2012, 12:28am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/97 "2012-01-21T00:28:38Z")
> [@Zeldar](#): > > Has anybody seen any Census Bureau data on this issue? Or some other large-scale and reliable source? I feel like I’m missing something here that you are trying to figure out. The article I linked earlier was a count of nearly 900,000 births over several years and also theorizes the deviations from the averages were due to elective inductions and c-sections, as I mentioned. What more do you want? Are you simply unable to accept that explanation? ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [January 21, 2012, 5:10am UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/98 "2012-01-21T05:10:35Z")
> [@USCDiver](#): > > I feel like I’m missing something here that you are trying to figure out. The article I linked earlier was a count of nearly 900,000 births over several years and also theorizes the deviations from the averages were due to elective inductions and c-sections, as I mentioned. > > What more do you want? Are you simply unable to accept that explanation? I’m looking for some large-scale study that compares favorably with our data. The article you linked to is off in several places, and other links I have checked either don’t have the full picture or are saying that Tuesday is the biggest day for births. I realize that it’s too early (300 votes or less) for our sample to be definitive, but I would expect a large-scale (thousands or tens-of-thousands) study to have some similarities to ours. So far I haven’t found such data reported in its entirety. As for accepting the explanation of why the weekend should be with lower numbers, I’d buy that our Saturday numbers are low, but Sunday is right at the “expected value” of 14.29% and that doesn’t square with the low weekend version. Color me skeptical that the Australian version is globally representative. ---
**Author:** ![USCDiver](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/uscdiver/32/354_2.png) [@USCDiver](https://boards.straightdope.com/u/USCDiver)\ **Post date:** [January 21, 2012, 1:59pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/99 "2012-01-21T13:59:30Z")
Oh, I see. I doubt such a study exists given our small sample size. The best I can say is that you shouldn’t expect a uniform distribution and leave it at that. ---
**Author:** ![Zeldar](https://avatars.discourse-cdn.com/v4/letter/z/b77776/32.png) [@Zeldar](https://boards.straightdope.com/u/Zeldar)\ **Post date:** [January 21, 2012, 2:18pm UTC](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396/100 "2012-01-21T14:18:20Z")
> [@USCDiver](#): > > Oh, I see. I doubt such a study exists given our small sample size. The best I can say is that you shouldn’t expect a uniform distribution and leave it at that. That much I’m ready to accept, so maybe somebody else’s data that pushes midweek (Wed-Thu) high will just have to do. 🙂 I do appreciate your input and expectations, and I didn’t/don’t mean to suggest the studies about non-natural childbirth are invalid. I’m sure there are rational reasons the 1/7 per day number isn’t working in our case. I’m still holding out a little hope that more votes will smooth our results, but I readily admit that hope is waning as time goes on. The Tuesday answer I keep finding elsewhere online for “heaviest day” just can’t be supported (yet) at SDMB. That’s all I feel confident about at this point. [Previous page](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396.md?page=4) [Next page](https://boards.straightdope.com/t/on-which-day-of-the-week-were-you-born/609396.md?page=6)