Control autoshape corner rounding for rounded rectangle in Word 2007

Yes, you can do it by dragging the yellow diamond handle that appears in the upper left once you have selected the shape.

Sourced from http://www.eggheadcafe.com/microsoft/Word-Drawing-Graphics/34093550/how-do-i-change-a-corner-radius-for-the-rounded-corner-rectangle.aspx.

I do not believe there is a precise way to do this, but sometimes I have a need to match the radius between different sized rounded rectangles. Let's say I have two rounded rectangles, A and B. If B is smaller or larger than A, then the radius is inherently different. To mitigate this, I make a copy of A and place it behind B. Then I use the yellow diamond to change the radius of B such that it perfectly matches A.