The Birthday Problem
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What is the probability that in a room of 25 people at least 2 people share the same birthday? What is your guess? Use the simulation below to empirically figure out the probability. |
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http://www-stat.stanford.edu/~susan/surprise/Birthday.html
Java problem? The link above still works using Seamonkey as the browser. Otherwise use:
https://spholmes.shinyapps.io/birthday_app/
Count the number of times you had
at least one match for each trial. What is the
percentage of successful matches to trials? (One or
more matches counts as only one match.)
Student
activity and collective crowd sourcing
Have students
collect the birthday data on several groups of 25 people.
These
people can be arbitrarily chosen as long as you
do not pay any attention to their birthdays
until you have the 25 people chosen. For example
you can choose the first 25 presidents of the
United States or any 25 from our current list of
46 presidents.
- Presidents
of the United States
- Members
of the New York Jets football team
- Members
of the New York Liberty basketball team
- Add your own group to this
list.
- Students in your schools classrooms. (Choose 25 members at random from a class list and find out their birthdates.)
See actual
probabilities - download
Excel file.
Teacher Page (coming soon)
Updated: 10/24/18
Updated: 10/24/18