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Subscribe to RSSExactly four years after a British mother gave birth to a pair of twin boys, on July 18, she delivered a second set of naturally conceived twins, according to a report Thursday in the British newspaper The Sun. The mom, Kim Hefer, is reportedly the first woman in the United Kingdom to have to two sets of twins on the same day years apart. A bookie set the odds of this happening at 30 million to one, the paper reported.
That’s only the most recent case of attention-grabbing coincidental births. A mother, daughter, and granddaughter all sharing the same birthday or twin sisters giving birth on the same day or a boy and girl born on the same day in the same hospital who grow up and decide to get married -- these odds-defying stories capture our imagination.
What is it about shared birthdays that are so irresistible?
Humans understand the world exists in certain ways; for example, we know that weather patterns, not angry gods, cause thunder. But something we perceive as coincidental, say a mother, daughter, and granddaughter sharing the same date of birth, seems so random to us so we believe that supernatural forces cause this coincidence.
“Basically any event is unlikely. If you flip a coin five times and it comes up heads each time, you think that something funny [has happened]. The probability of getting heads, heads, heads, heads, heads, is the same as any other sequence. It’s not that it is unlikely … there is something else about it that strikes us,” says Tom Griffiths, director of the Computational Cognitive Science Lab and the Institute of Cognitive Brain Sciences at the University of California, Berkeley.
Griffiths and his colleague wrote a paper, which explores coincidences and also considers “the birthday problem.” A classic statistical exercise, the birthday problem aimed to discover how many people needed to gather in a room for two to share a birthday. If there are only 23 people in a room, there is a 50 percent chance that two share a birthday and this likelihood increases as the number of pairs entering the room grows. Griffiths’ findings reinforce what experts know about the birthday problem—shared birthdays aren’t as random as we like to think.
“Why is it that people having the same birthday is something that strikes us? Is it that it suggests there is some underlying reasoning behind it? Our brains want to believe that it is something other than chance,” Griffiths says.
Atlanta psychologist Robert Simmermon agrees that people assign meaning to random events, believing God, fate, karma, or the stars contribute to chance.
“One in 30 million chances … that chance is incomprehensible,” says Simmermon, who has a private practice. “We really can’t understand anything else that might be like it.”
And people feel more intrigued by these birthday coincidences because birthdays carry a lot of emotional weight.
“It’s the genesis; it is the beginning,” he says. “The birthday is the beginning of our existence … well, the beginning of our consciousness.”
Do you share the same birthday as a sibling or other close family member? Share your unusual birthdate coincidences on Facebook
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Leave a Comment:
There's really nothing odd about shared birthdays, there are only 365 days in years versus thousands of people born in any given country and the millions born in the world every year.
I agree and think it's just that people identify with what is familiar to them. Simple as that. Just like when you find someone that has similar tastes in music, sport, art, etc.
I was the only person born on my day, year, and month, at my time of day, in my City, from my mother and father, nobody else can say that, I think! I was 0 at the time I'm just going on rummer here!
Bubba, its spelled r-u-m-o-r, might want to check a dictionary next time.
Pretty standard reason people are impressed. Most our high school graduates have almost no math skills so anything related to numbers is magic to them
It's just cool!! My birthdate is 6/6/65. I grew up with a girl whose birthday was 6/5/65. We thought it was a "neat thing" to have those birthdates and know each other.
The probability of flipping a fair coin five times and getting the sequence HHHHH is NOT the same as all the other combinations.
Really the chance of getting HHHHH is exactly the same as getting HTHTT. Both combinations have a 1 in 32 chance of happening. Each coin flip is an independent event and is not affected by the previous flips. Therefore you can just multiply the chances of each outcome to get your final probability. In other words, there is nothing magic about such an outcome.
No, but it's the same as any other particular combination that you choose. The "miracle", if there is one, is that we assign special meaning to HHHHH but no HTHHT for example. That's the point of the article. Las Vegas relies on people's ignorance of basic probability theory. This is why when they lose at slots they keep playing thinking that it will "even out eventually" if they have a long run of no winners. By extension, I think many have deep seated religious convictions and believe in miracles for precisely the same reason. The human brain is a pattern-generating machine. We find patterns even when they don't exist through the power of selective attention and biased memory.
My dad died on my birthday. One in 365 chance I guess.
one in 365.25
I have two daughters born on March 28th from two different mothers. One was born on Easter Sunday and the other was born on Good Friday, eight years apart. They have never shared a birthday celebration.
People are very bad at understanding randomness and tend to think that random events are more evenly distributed than they actually are. Because of this, people think small samples are more representative of their populations than they really are. This is why we need statistical significance tests.
I don't care if its statistically irrelevant, I love this stuff! My godson was born the same day as his cousin in the same hospital = sisters giving birth the same day. The odds were 8 million to one and they were on the news. Logic doesn't overpower my "thats pretty cool" feeling.
I don't have a birthday (Sniff.....).
?
My daughter (from my first marriage) was named after me. After her father and I divorced, I married a man whose mother has the same name and birthday as my daughter. What are the odds!? I should note that bothe the first and middle names are the same, not just the first names.
both
I took a probability and statistics class in college that used three intersecting circles to solve certain math questions. I loved that class.
"I Like Numbers, Do You Know Why ? "
"You Can Always Count On Them." Lame but couldn't resist.
I know, lame joke posted minutes ago. Sorry (No I'm not).
Seriously now, I had a twin who was stillborn . I'm not into Astrology ,our Horoscopes,or matters pertaining to it. However I know a couple people who were that became intriqued when learning my birthday. Wow, you're a Gemini and lost a twin! One was into reading twin books. One was a Landlady I rented from many years ago. She was part Indian and lived in the woods of Maine until she was 15. She and her husband were both fascinating people. She kept handing me "twin books" to read. One was about "The Power Twin" . The power twin is the twin who lost his/her twin at or before birth. The void felt , absorbing the energy or traits of their personalities , and things like feeling they are with you. An interesting read and it did make me think about my twin. I just didn't buy into it completely.
Now . Numerically not rare but I couldn't help notice that on three occasions after becoming best friends during different segments of my life one shared the same day, month,and year. The two others were just one day earlier . Not earth shattering news but interesting quirk. On other occasions I would find out that although not best friends but many people that I would be close to were within 7 days of my birthday . Just a weird quirk .
the article states the odds are "30 million to one" quoting an un-named "bookie". these are very slim odds. tossing coins or filling a room with 23 different people and determining odds is a whole different deal. tossing coins is a "trivial coincidence" (my term). the birth of twins on the same day as their sibling twins is another - I'd call this "non-trivial coincidence" (my term). The study, (not mentioned in the article) "Randomness and Coincidences: Reconciling Intuition and Probability Theory" by Thomas L. Griffiths and Joshua B. Tenebaum, Page 370 of the "Proceedings of the Twenty-Third Annual Conference of the Cognitive Science Society" does not discuss nor draw conclusions on "non-trivial coincidences". For the author to discuss "trivial" and "non-trivial" coincidences in the same article as if each were one and the same thing shows a gross lack of grasping the concept of science. It should be obvious by comparing the odds of the "coincidental" birth of the twins discussed in the article and the odds of tossing a coin that they are NOT the same thing. Nor, can we assume they belong in the same topic given the lack of necessary information in the article. I doubt seriously if anyone is just as surprised at flipping five heads in a row or discovering that at least two people share a birthday in a room of twenty-three as they are to this incredible "coincidence" of the twins birth. Sloppily written article: un-named sources and un-named study, slap a label on the whole thing (coincidences) and call it done.
The point of the article is precisely the fact that we distinguish between "trivial" and "non-trivial" coincidences at all. Almost any string of historical events has astronomical odds against it. For example, the odds that your parents would ever meet, that they would have sex, that a particular egg and a particular sperm would join to create you, collectively is so unlikely that it is nearly certain never to occur twice (i.e. to get a clone by chance). It seems miraculous until you consider that it is the same exact odds as any other birth. In this sense, miracles are ubiquitous and therefore all become trivial. The fact that we view things as "miraculous" at all is the miracle.
I was born on my mother's birthday. My husband and his younger son were born on the same day. My husband's older son and daughter are twins, and the older son and HIS son also share the same birthday, so that's 3 with the same birthday. That's quite a few shared birthdays in one family.
I disagree. If a woman has a regular ovulation cycle, then it really isn't that surprising. And with twins I am guessing that there might have been a scheduled C Section. Need more facts before getting all excited!
Scheduled C-section or not, it's unlikely enough to naturally conceive two sets of twins.
Think of all the amazing things people could read, do, experience, or create if they didn't spend time thinking about stupid crap like random coincidences...
Well I am privilege to announce that my sister has three kids that were born on January 15th[boy/girl twin and my little baby niece,who I might add is very talkative.She also has another set of boy/girl twin....
My grand mother God rest her soul has three kids[two adult male and a female all born in the month of March but different years.
"Why do we care about birthday coincidence?" Who is "we" ? I do not care about them. Coincidences happen. I remember, after one field work summation we found we had measured exactly 10 000 trees !
My sister and I have the same birthday and we are 2 years apart.
My husband's aunt had 2 sets of twins, and they share a birthday, and I think they are 7 years apart.
Obama's B.Day is Aug 4th coincidentally the Coast Guard celebrates their birthday on Aug 4th too.
My favorite state is Hawaii although i live in Florida . Coincidentally Obama was supposedly born there and grew up there.
I actually voted for him over Mc Cain at the last minute. Not sure about Romney i may get Obummer another chance.
My husband, me, our 3 children and 3 of our 4 grandchildren (3 generations) share our birthdays on the same day of the week every year. We have different birth years and dates, however, we will all celebrate on a Tuesday this year. Our 4th grandchild's birth was induced throwing off the pattern. LOL .... she's definately a "trend setter".
I have two coincidences
1. I had children the same day as my mother:
My mother had 2 children
One child was born on December 28 and the other on May 24.
I had 2 children.
One child was born on December 28 and the other on May 24.
Second coincidence:
My birthday is May 24
My daughter's birthday is May 24
My granddaughter's birthday is May 24
Coincidently The Chicago Bulls were going for a Three-Peat basketball championship, which The Chicago
Tribune wrote about , came, and took pictures of our "Three-Peat". The year was May, 1993...they won.