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The Birthday Paradox Experiment (2018)

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Re: The Birthday Paradox Experiment (2018)

#21

Post by unklefolk »

nuancebydefault wrote: post #16

I'm a bit confused. Maybe i did not pay enough attention but... Does it stop the first simulation when there are _any_ 2 people with a same birthday, or when someone has _my_ birthday? I think the latter will take more people on average.

The Birthday Paradox is about a group of people sharing at least one birthday between them. If it was at least 1 person out of 23 people sharing YOUR birthday then the odds would be 1 - (364/365)^23 which is around 0.06 (or 6% chance). So, yes, this scenario is a lot less likely.

Re: The Birthday Paradox Experiment (2018)

#22

Post by nuancebydefault »

unklefolk wrote: post #21
nuancebydefault wrote: post #16

I'm a bit confused. Maybe i did not pay enough attention but... Does it stop the first simulation when there are _any_ 2 people with a same birthday, or when someone has _my_ birthday? I think the latter will take more people on average.

The Birthday Paradox is about a group of people sharing at least one birthday between them. If it was at least 1 person out of 23 people sharing YOUR birthday then the odds would be 1 - (364/365)^23 which is around 0.06 (or 6% chance). So, yes, this scenario is a lot less likely.

Thanks for that. I believe the fact that it asks for a birthday puts people's brain in a mode where the awe at the end is bigger.

Related, having flat tires on a car seems to come in little bursts,like 10 years none and then 2 in a year.

Re: The Birthday Paradox Experiment (2018)

#24

Post by tosser0001 »

An analog of the birthday paradox that gets me all the time is what I think of as The Locker Room Paradox. This is where when I go into the locker room after working out and the guy who comes in behind me ends in the locker right next to mine. So there’s two of us in a big empty room awkwardly jostling away.

Re: The Birthday Paradox Experiment (2018)

#25

Post by DiscourseFan »

tosser0001 wrote: post #24

An analog of the birthday paradox that gets me all the time is what I think of as The Locker Room Paradox. This is where when I go into the locker room after working out and the guy who comes in behind me ends in the locker right next to mine. So there’s two of us in a big empty room awkwardly jostling away.

>awkwardly jostling away

I imagine it’d be more fun in a group setting?

Re: The Birthday Paradox Experiment (2018)

#26

Post by profsummergig »

bambax wrote: post #17
bsimpson wrote: post #3

It's interesting how uniform the birthday distribution at the end looks. I'd expect more seasonality (e.g. more babies conceived in the cold, dark months).

Yes, it's also extremely unlikely. The actual distribution in developed countries is not uniform: there is a spike at the end of September (because many more people make babies at or around New Year's Eve) and a considerable drop on Dec. 25th (because people will avoid that date and provoque the birth some days before in case it might happen). Also, on the site there is a huge spike on Nov. 15 which, incidentally, is…

Why do people not like having their child be born on Xmas?

Re: The Birthday Paradox Experiment (2018)

#27

Post by Miraltar »

bambax wrote: post #17
bsimpson wrote: post #3

It's interesting how uniform the birthday distribution at the end looks. I'd expect more seasonality (e.g. more babies conceived in the cold, dark months).

Yes, it's also extremely unlikely. The actual distribution in developed countries is not uniform: there is a spike at the end of September (because many more people make babies at or around New Year's Eve) and a considerable drop on Dec. 25th (because people will avoid that date and provoque the birth some days before in case it might happen). Also, on the site there is a huge spike on Nov. 15 which, incidentally, is…

15th november are valentine's babies, I'm not surprised about this spike

Re: The Birthday Paradox Experiment (2018)

#28

Post by boomboomsubban »

Miraltar wrote: post #27
bambax wrote: post #17

Earlier quoted context omitted.

Yes, it's also extremely unlikely. The actual distribution in developed countries is not uniform: there is a spike at the end of September (because many more people make babies at or around New Year's Eve) and a considerable drop on Dec. 25th (because people will avoid that date and provoque the birth some days before in case it might happen). Also, on the site there is a huge spike on Nov. 15 which, incidentally, is…

15th november are valentine's babies, I'm not surprised about this spike

Any such spike would be over weeks, not heavily concentrated on one day. It's clearly people taking the quiz twice to see what it says if you match the creators birthday.

Re: The Birthday Paradox Experiment (2018)

#29

Post by jll29 »

phito wrote: post #8

I really like the fact that it's using the previous user birthdays. Unfortunately today is my birthday and I think a lot of people are entering today's date as their birthday, I got 6 matches... :)

Plenty of November birthdays because it's cold in Februrary (11 - 9 = 2).
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