When we model put delta this means the estimated delta (directional exposure) positioning from dealer (market maker) puts. 

The positioning of a put has everything to do with its deltas. Out-of-the-money puts have lower deltas. At-the-money puts have about 50 delta, and in-the-money puts have higher deltas (going up to 100). For our put delta calculation, the total number of all puts are added up as positive deltas from a dealer perspective because we consistently model dealers to be short puts on both index products and stocks.