Power parameter and IDW

Discussion created by bill.gaertner on Mar 3, 2014
Latest reply on Mar 4, 2014 by bill.gaertner
I am working on an analysis that involves polygons and points with values and I am using IDW to predict the values of pixels in between.  I need the values of the points to have a 50% impact on the values of the surrounding pixels when they are 3 miles away from the source data and a 0% impact when they are 5 miles away.  I am wondering if anyone knows of a formula I could use to determine what power value would get me the results I am looking for.  I'm basing this slightly off of a graph that is on one of the help pages for the IDW tool, a copy of which is attached.  I'm hoping that there is a formula that would generate those different curves.

Is this possible or does anyone have any ideas?