I am looking for the best way to describe in a report what I am observing in a experiment.
There are cars (or objects) in front of me, and my system is inferring a property of them (for example their direction). The inferences of the objects right in front of me are quite accurate (so the error is 0). However, the inference of the object 5 meters to the left has a small error. The inference of the object 5 meters to the right has almost the same small error (but negative). The inference of the object 10 meters to the left has a bigger error (same as 10 meters to the right).
I want to convey in a paragraph that I have observed this tendency, that the system's inferences have an error that is kind of proportional to how far the object is from the center. I am tempted to use the word "displacement", as in displacement proportional to the distance from the center. How can I convey this in technical writing?