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I'm dealing with spatial interpolation methods, in particular with the weighted moving average. I come across really oft with a term "duck egg patterns" which are caused by isolated data points.

Does any one has an idea what do they mean. What do duck eggs look alike? (not different as any other egg.....).

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Can you provide a link to where you have come across this term ? – PolyGeo Feb 24 '14 at 20:04
up vote 5 down vote accepted

If you follow this link you will see some duck eggs. Even if in this case it comes from inverse distance weight and not from weighted moving average. It is quite common with those two interpolation methods.

You have ellipse or circles around your isolated point, which are different from the background and therefore very visible. This is necessary the case when the neighborhood only includes one point: the elliptic shape will occur when you still have a small influence from far away neighbours, and the circle when there is nothing else around.

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