[math] Poisson distribution

 

• Lambda is the average.

• k is the number you are guessing will happen.

Example:

Hash Table Collisions

While hash functions aim for uniformity, the number of keys that map to a specific "bucket" in a large hash table can be modeled using Poisson.

• If you have n keys and m buckets, and n/m is small, the number of items in a bucket follows a Poisson distribution with Lambda = n/m

• This helps in estimating the frequency of collisions and optimizing the size of the table.