我必须通过收缩因子(lambda)将方差 - 协方差矩阵中的值缩小到方差(矩阵中的对角线值),因此:lambda * shrinkagematrix +(1-lambda)* variancecovariancematrix,其中:
方差协方差矩阵是:
Function VarCovar(rng As Range) As Variant
Dim i As Integer
Dim j As Integer
Dim numcols As Integer
numcols = rng.Columns.Count
numrows = rng.Rows.Count
Dim matrix() As Double
ReDim matrix(numcols - 1, numcols - 1)
For i = 1 To numcols
For j = 1 To numcols
matrix(i - 1, j - 1) = Application.WorksheetFunction.Covar(rng.Columns(i), rng.Columns(j)) * numrows / (numrows - 1)
Next j
Next i
VarCovar = matrix
,这给了我一个矩阵,看起来像这样的例子:
0.40 -0.10 0.11
-0.10 0.17 -0.03
0.11 -0.03 0.19
然后我在创建Shrinkage矩阵时遇到问题,该矩阵看起来像:
0.40 0.00 0.00
0.00 0.17 0.00
0.00 0.00 0.19
即仅返回对角线值(=变量的方差)和所有其他单元格中的零。
因此,以某种方式,使其返回仅包含row =列号的值的矩阵,即(1,1),(2,2)和(3,3)值。
有人可以帮忙吗?
你只需要一个从i = 1 to 3
计算的循环来填充Matrix(1, 1)
,Matrix(2, 2)
和Matrix(3, 3)
使用Matrix(i, i)
Function VarCovar(InputMatix As Range) As Variant
Dim MatrixColumns As Long
MatrixColumns = InputMatix.Columns.Count
Dim MatrixRows As Long
MatrixRows = InputMatix.Rows.Count
Dim Matrix() As Double
ReDim Matrix(1 To MatrixColumns, 1 To MatrixColumns)
Dim i As Long
For i = 1 To MatrixColumns
Matrix(i, i) = Application.WorksheetFunction.Covar(InputMatix.Columns(i), InputMatix.Columns(i)) * MatrixRows / (MatrixRows - 1)
Next i
VarCovar = Matrix
End Function
请注意,我更改了qazxsw poi维度qazxsw poi以qazxsw poi而不是Matrix
开头,因此您可以轻松地将其用于将其写入单元格:
Matrix(1 To MatrixDimension, 1 To MatrixDimension)