#### Immediate family (5 people)

{{ group_of_5 }} ({{ odds_are_like_5 }})

#### Close friends (15)

{{ group_of_15 }} ({{ odds_are_like_15 }})

#### Friends (50)

{{ group_of_50 }} ({{ odds_are_like_50 }})

#### Acquaintances (150)

{{ group_of_150 }} ({{ odds_are_like_150 }})

#### People you know (500)

{{ group_of_500 }} ({{ odds_are_like_500 }})

#### Meet during your lifetime (80,000)

{{ group_of_80000 }} ({{ odds_are_like_80000 }})

"Dunbar" numbers are based on the theories and research of Robin Dunber, who was attempting to show that humans have hardwired limits on the numbers of people that they can know and with whom they can have effective relationships. While this is far from settled science, and there are many great arguments against his work, it's instructive to use as a framework here. I am using Dunbar-derivative group sizes for the different odds, and assigning a plain language description to each purely to help with fast comprehension by most people. It's not intended to be scientifically accurate, but a fun and interesting point of conversation.

The odds are based on a uniform distribution of people into all of the stated groups, and we know that doesn't happen. It's reasonable to assume that people tend to cluster on an IQ basis somewhat for peer groups. Also, IQ is highly heritable (0.75-0.80) once humans have reached adulthood, so the "family" grouping isn't subject to a uniform distribution either. But once again, this is just supposed to be fun!