However, the deviation is also subject to the weighting function before the error function is computed.

Some common local weighting functions are defined in the following table.

The choice of weighting function will be discussed later.

With the weighting function, the summation can be replaced by a contour integral in the complex plane.

As in Fig. 1, the weighting function generates poles (red crosses) on the imaginary axis.

So as to control the convergence, the weighting function of the first type is always chosen .

Mathematically, the moving average is the convolution of the datum points with a fixed weighting function.

Each weighting function or "kernel" has its own characteristics.

Additionally, the communities found in the network are highly dependent on the choice of weighting function.

For the purpose of facilitating the expression, a weighting function is defined: