Sorts in descending order by location boosted yield. The 'boost' score is ~25% boost for a closer geographic locational match.
Scenario 1
Advertiser A bids $1 for the location 'NY'
Advertiser B bids $0.8 for the location 'New York City'
Outcome
An Ad request for 'New York City' will return Advertiser B before Advertiser A.
Further Information
The location boosting of 25% offsets the bid price of Advertiser B of $0.80 by $0.20 thereby making the 'relevancy-determinant bid' akin to $0.80 + $0.20 = $1.00 .