How can I calculate the average of a field in specific polygons and add that average on the nearest street? For example i calculated betweenness centrality at each polygon for a city (polygons-> buildings) and i want to add the average of the betweenness

[CHARALAMPOSLEPENIOTIS]

For the example, I want to calculate the average of the row of the orange buildings and this number i want to put it on the front street

[DanPatterson_Retired]

spatially join the polygons to the polyline assuming the attribute you need is in the polygons