# Extensions of the birthday surprise

@article{Klamkin1967ExtensionsOT, title={Extensions of the birthday surprise}, author={Murray S. Klamkin and Donald J. Newman}, journal={Journal of Combinatorial Theory, Series A}, year={1967}, volume={3}, pages={279-282} }

Abstract The so-called “birthday surprise” is the fact that, on the average, one need only stop about 24 people at random to discover two who have the same birthday. Here we determine, asymptotically, the expected number of people in order for n of them to have the same birthday. In particular, for three birthdays, it is about 83 people.

## 77 Citations

The matching, birthday and the strong birthday problem: a contemporary review

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- 2005

This article provides a contemporary exposition at a moderately quantitative level of the distribution theory associated with the matching and the birthday problems. A large number of examples, many…

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- Computer Science2017 IEEE Symposium on Computers and Communications (ISCC)
- 2017

A new non-recursive approximation for the birthday probability applicable to any value of m > 1 is presented, which yields results that are experimentally proven accurate under the assumption that the number of birthdays is significantly larger than thenumber of people.

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- 2003

We study the birthday problem and some possible extensions. We discuss the unimodality of the corresponding exact probability distribution and express the moments and generating functions by means of…

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- 1991

The paper deals with the expected number of trials in the birthday problem. Two possible models are studied, corresponding to different methods of computer simulation. The problem of finding moments…

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This paper considers generalizations of two classical probability problems: the birthday problem and the coupon collector's problem in terms of urn models and captured through generating functions.

Solutions of Some Birthday Problems Using Dirichlet Integrals

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ABSTRACT We solve many different interesting birthday problems using Dirichlet functions (I, J, C, D). Some of them are very well-known classical problems which we generalize. These solutions are…

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Consider a uniformly random deck consisting of cards labelled by numbers from 1 through n, possibly with repeats. A guesser guesses the top card, after which it is revealed and removed and the game…

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Motivated by the more frequent natural and anthropogenic hazards, we revisit the problem of assessing whether an apparent temporal clustering in a sequence of randomly occurring events is a genuine…

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This entry provides a contemporary exposition at a moderately quantitative level of the distribution theory associated with sequences and patterns in iid multinomial trials, the birthday problem, and…

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This article provides a contemporary exposition at a moderately quantitative level of the distribution theory associated with sequences and patterns in iid multinomial trials, the birthday problem,…

## References

The Double Dixie Cup Problem

- Mathematics
- 1960

The familiar childhood occupation of obtaining a complete set of pictures of baseball players, movie stars, etc., which appear on the covers of dixie cups raises some interesting questions. One,…