Statistical oddity

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  • LCHIEN
    Internet Fact Checker
    • Dec 2002
    • 20914
    • Katy, TX, USA.
    • BT3000 vintage 1999

    Statistical oddity

    Click image for larger version  Name:	no birthdays today.JPG Views:	0 Size:	37.7 KB ID:	845937
    As many registered users as we have, its seems a statistical oddity that no one has a birthday today!
    We have over the years gotten 1833 pages of registered users in the member list, at 10 per page that's 18,330 users.
    If birthdays were evenly distributed there should be 50 members with birthdays today.
    Perhaps the entry of BD is optional? I can't recall its been so many years since I registered. But even if 1 of 5 supplies a birthdate then there should be 10.



    Last edited by LCHIEN; 11-05-2021, 11:10 PM.
    Loring in Katy, TX USA
    If your only tool is a hammer, you tend to treat all problems as if they were nails.
    BT3 FAQ - https://www.sawdustzone.org/forum/di...sked-questions
  • twistsol
    Veteran Member
    • Dec 2002
    • 2893
    • Cottage Grove, MN, USA.
    • Ridgid R4512, 2x ShopSmith Mark V 520, 1951 Shopsmith 10ER

    #2
    To show up on the list, the third or fourth option must be selected in the privacy setting for birthdays on your user profile. Additionally, you must have at least one post to show as well.

    Click image for larger version

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    Chr's
    __________
    An ethical man knows the right thing to do.
    A moral man does it.

    Comment


    • LCHIEN
      LCHIEN commented
      Editing a comment
      So maybe only 10% of the 18,000 registered meet the criteria, esp. having had more than one post.
      I wondered after I posted the comment why there weren't usually 10-50 birthday people listed every day.
      But its probably still a low chance of no one having a birthday on a given date.
  • leehljp
    Just me
    • Dec 2002
    • 8429
    • Tunica, MS
    • BT3000/3100

    #3
    I have forgotten the specific statistic on birthdays, but it is something along the line of "20". If one has a group of 20 (could be 22) there will be a very high probability of 2 having the same birthday.


    Speaking of birthdays, how many people do you know with the same birthday as yours?
    Hank Lee

    Experience is what you get when you don't get what you wanted!

    Comment

    • cwsmith
      Veteran Member
      • Dec 2005
      • 2737
      • NY Southern Tier, USA.
      • BT3100-1

      #4
      In my 77 years, I've only known one person. In the summer of 1963 I spent a few weeks at Griffiss AFB and there I met a young lady with the same birhday. While our names were completely different, our initials were the same.

      Speaking of names, there are thousands of 'Charlie Smith's in this world, and so my father was insistant that I always use my middle initial. So here in Broome County, NY when I was growing up, I was the only 'Charles W Smith' and that included the two adjacent counties (at least those names listed in the phone directory). But in 1973, when I took a job with Ingersoll-Rand in Painted Post, NY (75 miles west of Binghamton) I was the third employee with that name. Fortunately, I had the distinction of being the only "William".

      CWS
      Think it Through Before You Do!

      Comment

      • atgcpaul
        Veteran Member
        • Aug 2003
        • 4055
        • Maryland
        • Grizzly 1023SLX

        #5
        I've known only one person with my birthday, but my cousin's birthday is 2 days before mine, my best man's birthday is one day before mine, and my Mom's is 2 days after mine.

        In another cousins' family, two of the siblings have the same birthday and their other sibling is only a few days away in the same month. Maybe not coincidentally, their parents' wedding anniversary is 9-10 months before.

        Comment


        • atgcpaul
          atgcpaul commented
          Editing a comment
          I forgot about my cousin on my Dad's side. He is one day older than me--beat me to oldest grandchild on my Father's side by a day.

          Oh, and my coworker's daughter and my daughter were born on the exact same day in the exact same hospital. That year, my office had about 7 babies amongst 100 or so office mates which seems like a lot to me.
      • leehljp
        Just me
        • Dec 2002
        • 8429
        • Tunica, MS
        • BT3000/3100

        #6
        I guess I am unusual. My best friend growing up had the same birthday as me; he was two years younger but both of us being rural and the same interests, we did a lot of things together and were in each others wedding.
        • I have a first cousin with the same birthday (12 years younger)
        • a second cousin 15 years older
        • a class mate with the same birthday
        • 2 other business people in my hometown with the same birthday. (I came in late to Jr Chamber of Commerce meeting once, and as I entered they began singing "Happy Birthday". I thought it was for me until I heard their names and saw them being congratulated! I never did tell them it was mine also.)
        • When in Japan, my first Japanese language teacher had the same birthday
        • the daughter of one of our church members in Osaka had the same birthday
        • The school where my middle daughter taught (in Japan); she taught a student with the same birthday. Her family were friends of ours over there. We exchange greetings through FB on occasion.
        • Two of my co-worker Missionaries in Japan had the same birthday; One has passed on, but the other lives about 75 miles from me today. The one that passed was about 20 years older and his wife still calls me on my birthday with birthday wishes. The first church I pastored (in Texas) was his first church also - 20 years before me.

        Most of us stay in touch and send birthday greetings.

        AND two famous people (now deceased) had this birthday - Elvis and Steven Hawkin
        Last edited by leehljp; 11-06-2021, 03:30 PM.
        Hank Lee

        Experience is what you get when you don't get what you wanted!

        Comment

        • LCHIEN
          Internet Fact Checker
          • Dec 2002
          • 20914
          • Katy, TX, USA.
          • BT3000 vintage 1999

          #7
          Elvis and Stephen Hawkins were born on the same day? What a cosmic coincidence!
          Loring in Katy, TX USA
          If your only tool is a hammer, you tend to treat all problems as if they were nails.
          BT3 FAQ - https://www.sawdustzone.org/forum/di...sked-questions

          Comment

          • capncarl
            Veteran Member
            • Jan 2007
            • 3564
            • Leesburg Georgia USA
            • SawStop CTS

            #8
            Where I worked there were 3 of us with the same birthday. One was a lady the same birth year also. She also knew a lot of my school classmates and other friends, and we had never met except for our job. Her and her husband are still good friends of ours

            Comment

            • radhak
              Veteran Member
              • Apr 2006
              • 3058
              • Miramar, FL
              • Right Tilt 3HP Unisaw

              #9
              Originally posted by leehljp
              I have forgotten the specific statistic on birthdays, but it is something along the line of "20". If one has a group of 20 (could be 22) there will be a very high probability of 2 having the same birthday.


              Speaking of birthdays, how many people do you know with the same birthday as yours?
              My favorite stat to start a conversation (or argument)!

              In a room of 23 people there’s a 50-50 chance of at least two people having the same birthday.
              In a room of 75 people there’s a 99.9% chance of at least two people matching.


              The reason people disbelieve this at first is that everyone thinks only of themselves - they think the claim is that there's a 50-50 or 99.9 chance their birthday matches someone else's in that room, when actually there are 22 (or 74) others who could match among themselves.
              It is the mark of an educated mind to be able to entertain a thought without accepting it.
              - Aristotle

              Comment

              • leehljp
                Just me
                • Dec 2002
                • 8429
                • Tunica, MS
                • BT3000/3100

                #10
                My favorite stat to start a conversation (or argument)!

                In a room of 23 people there’s a 50-50 chance of at least two people having the same birthday.
                In a room of 75 people there’s a 99.9% chance of at least two people matching.
                23, not 22! But that is not bad since it has been probably 20 something years since I read that. Thanks!
                Hank Lee

                Experience is what you get when you don't get what you wanted!

                Comment

                • cwsmith
                  Veteran Member
                  • Dec 2005
                  • 2737
                  • NY Southern Tier, USA.
                  • BT3100-1

                  #11
                  I guess I would have to question that statistic. In one of my earlier jobs, back in the mid-60's I worked in the home office of an insurance company, where they published a very professional looking weekly newsletter. With approximately 400 employees in that office no one shared my birthday or my wife's. Later when I worked at Ingersoll-Rand, none of the Engineering office area (approx 80 people) shared my birthday. There were a few that shared other birthdays though and a few had a birthday on the day before or after mine. One of my nieghbors had a birthday after mine. And in our family (Aunts, Uncles, Cousins, and their husbands and wives, I don't know of any shared birthdays... that's more than forty of us. They're all a very close Italian family with the grandparents and some of the Aunts and Uncles being born in Italy... they're all pretty close, so I think we would be aware.

                  Regarding the forum membership, it would be nice to know how many have posted their birth date. Some days there are none and days like today, there is only one listed birthday.

                  CWS
                  Think it Through Before You Do!

                  Comment

                  • atgcpaul
                    Veteran Member
                    • Aug 2003
                    • 4055
                    • Maryland
                    • Grizzly 1023SLX

                    #12
                    Originally posted by radhak
                    The reason people disbelieve this at first is that everyone thinks only of themselves - they think the claim is that there's a 50-50 or 99.9 chance their birthday matches someone else's in that room, when actually there are 22 (or 74) others who could match among themselves.

                    Originally posted by cwsmith
                    I guess I would have to question that statistic.
                    For me personally, that stat doesn't apply, but I was just thinking that my wife's birthday is the same as my Uncle's as well as 2 of my co-workers.

                    Comment

                    • leehljp
                      Just me
                      • Dec 2002
                      • 8429
                      • Tunica, MS
                      • BT3000/3100

                      #13
                      . . . Well, some people have 3 birthdays!
                      We had a retired Korean American couple (Mr. and Mrs. Lee - we told everyone we were cousins) come to Japan to work with us for 6 years. Mr. Lee was born when Korea was Japan territory (1929) and he lived in what later became North Korea. (He later escaped to South Korea as a teenager). Anyway, His wife invited us over to His celebrate his birthday. We went and enjoyed it. Then a week later she said it was Mr. Lee's birthday again. I asked how that could be, and then she said he had 3 birthdays.

                      1. The day when He was actually born.
                      2. Rural & small community births were registered when the local officials went to provincial towns to record the births. The births were listed for the day they were officially recorded, not when they were born.
                      3. Some local areas acknowledged a "season" and all within a specific season were acknowledged together on a specific day.
                      How accurate the last one is, I am not sure, as there could have been some ambiguity in the description and hearer. My wife heard the same but it did not make complete sense to us.

                      CWS: The stats are correct, all of your family stats got taken away and given to me. (Joking). It's like losing the coin toss 10 times in a row (it happens) and another person wins 8 out of 10!
                      Last edited by leehljp; 11-07-2021, 04:38 PM.
                      Hank Lee

                      Experience is what you get when you don't get what you wanted!

                      Comment

                      • LCHIEN
                        Internet Fact Checker
                        • Dec 2002
                        • 20914
                        • Katy, TX, USA.
                        • BT3000 vintage 1999

                        #14
                        Originally posted by radhak

                        My favorite stat to start a conversation (or argument)!

                        In a room of 23 people there’s a 50-50 chance of at least two people having the same birthday.
                        In a room of 75 people there’s a 99.9% chance of at least two people matching.


                        The reason people disbelieve this at first is that everyone thinks only of themselves - they think the claim is that there's a 50-50 or 99.9 chance their birthday matches someone else's in that room, when actually there are 22 (or 74) others who could match among themselves.
                        Yes the reason is that the chance of one specific day, yours or any specific day like Christmas or a randomly chosen day is small, only one in 365.

                        But the chances increase when there are 22 more chances and it can be any day not a specific day.

                        Its sort of like the chances is all heads in 20 tosses of a coin is around 1 in a million.
                        But there's nothing special about all heads compared to any other specific sequence of 20 tosses, the same probability, 20 heads is not special its just one of about 1,000,000 (actually 1,048,576) unique possible outcomes.
                        Loring in Katy, TX USA
                        If your only tool is a hammer, you tend to treat all problems as if they were nails.
                        BT3 FAQ - https://www.sawdustzone.org/forum/di...sked-questions

                        Comment

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