Just For Fun! - Statistics (1 of 2) The Probability of 2 People Having the Same Birthday

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  • Опубликовано: 4 янв 2025

Комментарии • 24

  • @asshwinm
    @asshwinm 9 лет назад +1

    i just love this playlist

  • @angry.sparrow
    @angry.sparrow 2 года назад +2

    great video!

  • @janpvp5955
    @janpvp5955 3 года назад +1

    How do you change this equation when you want to find out how many people you need for a 50% chance?

    • @MichelvanBiezen
      @MichelvanBiezen  3 года назад +1

      It would be easier to change n and use trial and error.

    • @janpvp5955
      @janpvp5955 3 года назад

      First of all: Thank you very much for the reply. I have a task to do, where I have to do the calculation that I described and I didnt find anything on the web, it does seem extremely hard.

    • @MichelvanBiezen
      @MichelvanBiezen  3 года назад +1

      Yes, you could place the 50% on the other side of the equal sign and then solve for n. But I think it would be easier to plug in different values for n and then zero in on the correct value. That is by the way a perfectly legitimate way of doing it. Ask your teacher if that will be acceptable.

  • @MarkAllen1
    @MarkAllen1 9 лет назад +2

    It is funny that it only needs 57 to get 99% chance, but 366 to get 100% chance!

    • @bildanielson
      @bildanielson 9 лет назад +1

      +Mark Allen lol..not this year! Need 367 for certainty.

    • @skwurtl
      @skwurtl 4 года назад

      @@enderyu there are only 366 days in a leap year, so you'd need 367 to guarantee two people having the same birthday

  • @maighe_tv2848
    @maighe_tv2848 2 года назад +1

    i think the introduction is misleading. this is not the probability that someone in the room has the same birthday as you, rather this is the probability of 2 random people in the room having the same birth date.

    • @MichelvanBiezen
      @MichelvanBiezen  2 года назад +2

      That is correct.

    • @alanrapoport2090
      @alanrapoport2090 Год назад

      maighe spot on. In truth birthday problems and their analogs are endless. One I like hard to find in print is the following: given the 23 people randomly selected what is the P of finding EXACTLY 2 with the same birthday? Before cerebrating take a guess(thinking fast as per Daniel Kahneman). Cryptic hint: I recall that I read that 23 has 1255 partitions; so exactly 2 and all the rest different is just one of those 1255 partitions, more or less.(could be two fives or two elevens or two twenty ones).

    • @alanrapoport2090
      @alanrapoport2090 Год назад

      Oops not two 21’s.

    • @maighe_tv2848
      @maighe_tv2848 Год назад

      @@alanrapoport2090 who asked

    • @alanrapoport2090
      @alanrapoport2090 Год назад

      Whoever.

  • @thelord2017
    @thelord2017 9 лет назад +1

    cool

  • @HeisenMgh
    @HeisenMgh 9 лет назад +1

    First :)