Each horizontal line of points in the graph appears to have the same Measured value on the y-axis (or very close to equal). However, they each have a different Predicted value on the x-axis.
Having many repeated values in the field you used to interpolate would produce this kind of graph. This isn't necessarily a problem, but you should look into it and confirm that the repeated values are expected in your data.
Each horizontal line of points in the graph appears to have the same Measured value on the y-axis (or very close to equal). However, they each have a different Predicted value on the x-axis.
Having many repeated values in the field you used to interpolate would produce this kind of graph. This isn't necessarily a problem, but you should look into it and confirm that the repeated values are expected in your data.
