I am trying to add the exact same process used when you right click and join a polygon to point layer. I want that same dialog box for parameters. Is that even possible? When I try Add Join or Spatial Join, it doesn't give me the ability to choose the same options as Join Data does....
Basically I am taking a polygon layer and joining it to a point layer, where each polygon will be given a summary of the attributes of points that fall inside it, using either SUM or AVG to summarize the data.
Have you tried Using the field mapping control—Help | ArcGIS for Desktop
I believe adding a Integer (Short or Long) or Double field will allow you to calculate SUM, AVG to summarize the data.
I hope this helps!