Hello,
i have the problem to simplify a formula to calculate the correlation of a portfolio and another share. I can calculate it step by step, but if has to be possible, to write an universal formula. Even if anybody could only name the necessary command, it would be easier to find a clue for the solution.
I calculate the correlation with the formula
p=[(correlation 1xn-vector) x (VaR nx1 vector transpose)]/square root[(VaR 1xn-vector) x (R nxn correlation-matrix) x (VaR nx1-vector transpose)]
R is the correlation-matrix of 10 shares
R={{1, 0.2808, 0.3211, 0.1329, 0.2887, 0.4646, 0.3683, 0.2544, 0.1663,
0.2745}, {0.2808, 1, 0.3632, 0.3754, 0.3197, 0.5202, 0.4083, 0.2652,
0.2225, 0.285}, {0.3211, 0.3632, 1, 0.3045, 0.4577, 0.5539, 0.4062,
0.4089, 0.3118, 0.4914}, {0.1329, 0.3754, 0.3045, 1, 0.2911,
0.3297, 0.2492, 0.3412, 0.1141, 0.3737}, {0.2887, 0.3197, 0.4577,
0.2911, 1, 0.5293, 0.4529, 0.5554, 0.4132, 0.643}, {0.4646, 0.5202,
0.5539, 0.3297, 0.5239, 1, 0.5918, 0.4585, 0.3148, 0.4844}, {0.3683,
0.4083, 0.4062, 0.2492, 0.4529, 0.5918, 1, 0.3787, 0.4705,
0.3896}, {0.2544, 0.2652, 0.4089, 0.3412, 0.5554, 0.4585, 0.3787, 1,
0.3297, 0.6272}, {0.1663, 0.2225, 0.3118, 0.1141, 0.4132, 0.3148,
0.4705, 0.3297, 1, 0.3033}, {0.2745, 0.285, 0.4914, 0.3737, 0.643,
0.4844, 0.3896, 0.6272, 0.3033, 1}}
VaR ist the Value at risk vector of the 10 shares
VaR={{1, 2, 3, 4, 5, -1, -2, -3, -4, -5}}
korrelation12zu3 = ({{R[[1, 3]],
R[[2, 3]]}}.{{VaR[[1, 1]]}, {VaR[[1,
2]]}})/\[Sqrt]({{VaR[[1, 1]], VaR[[1, 2]]}}.{{R[[1, 1]],
R[[1, 2]]}, {R[[2, 1]],
R[[2, 2]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}})
{{0.423316}}
korrelation123zu4 = ({{R[[1, 4]], R[[2, 4]],
R[[3, 4]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1,
3]]}})/\[Sqrt]({{VaR[[1, 1]], VaR[[1, 2]],
VaR[[1, 3]]}}.{{R[[1, 1]], R[[1, 2]], R[[1, 3]]}, {R[[2, 1]],
R[[2, 2]], R[[2, 3]]}, {R[[3, 1]], R[[3, 2]],
R[[3, 3]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1, 3]]}})
{{0.388424}}
korrelation1234zu5 = ({{R[[1, 5]], R[[2, 5]], R[[3, 5]],
R[[4, 5]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1, 3]]}, {VaR[[
1, 4]]}})/\[Sqrt]({{VaR[[1, 1]], VaR[[1, 2]], VaR[[1, 3]],
VaR[[1, 4]]}}.{{R[[1, 1]], R[[1, 2]], R[[1, 3]],
R[[1, 4]]}, {R[[2, 1]], R[[2, 2]], R[[2, 3]],
R[[2, 4]]}, {R[[3, 1]], R[[3, 2]], R[[3, 3]],
R[[3, 4]]}, {R[[4, 1]], R[[4, 2]], R[[4, 3]],
R[[4, 4]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1,
3]]}, {VaR[[1, 4]]}})
{{0.481585}}
korrelation12345zu6 = ({{R[[1, 6]], R[[2, 6]], R[[3, 6]], R[[4, 6]],
R[[5, 6]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1, 3]]}, {VaR[[
1, 4]]}, {VaR[[1, 5]]}})/\[Sqrt]({{VaR[[1, 1]], VaR[[1, 2]],
VaR[[1, 3]], VaR[[1, 4]], VaR[[1, 5]]}}.{{R[[1, 1]], R[[1, 2]],
R[[1, 3]], R[[1, 4]], R[[1, 5]]}, {R[[2, 1]], R[[2, 2]],
R[[2, 3]], R[[2, 4]], R[[2, 5]]}, {R[[3, 1]], R[[3, 2]],
R[[3, 3]], R[[3, 4]], R[[3, 5]]}, {R[[4, 1]], R[[4, 2]],
R[[4, 3]], R[[4, 4]], R[[4, 5]]}, {R[[5, 1]], R[[5, 2]],
R[[5, 3]], R[[5, 4]],
R[[5, 5]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1,
3]]}, {VaR[[1, 4]]}, {VaR[[1, 5]]}})
{{0.675596}}
korrelation12346zu7 = ({{R[[1, 7]], R[[2, 7]], R[[3, 7]], R[[4, 7]],
R[[5, 7]],
R[[6, 7]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1, 3]]}, {VaR[[
1, 4]]}, {VaR[[1, 5]]}, {VaR[[1, 6]]}})/\[Sqrt]({{VaR[[1, 1]],
VaR[[1, 2]], VaR[[1, 3]], VaR[[1, 4]], VaR[[1, 5]],
VaR[[1, 6]]}}.{{R[[1, 1]], R[[1, 2]], R[[1, 3]], R[[1, 4]],
R[[1, 5]], R[[1, 6]]}, {R[[2, 1]], R[[2, 2]], R[[2, 3]],
R[[2, 4]], R[[2, 5]], R[[2, 6]]}, {R[[3, 1]], R[[3, 2]],
R[[3, 3]], R[[3, 4]], R[[3, 5]], R[[3, 6]]}, {R[[4, 1]],
R[[4, 2]], R[[4, 3]], R[[4, 4]], R[[4, 5]],
R[[4, 6]]}, {R[[5, 1]], R[[5, 2]], R[[5, 3]], R[[5, 4]],
R[[5, 5]], R[[5, 6]]}, {R[[6, 1]], R[[6, 2]], R[[6, 3]],
R[[6, 4]], R[[6, 5]],
R[[6, 6]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1,
3]]}, {VaR[[1, 4]]}, {VaR[[1, 5]]}, {VaR[[1, 6]]}})
{{0.511916}}
korrelation123467zu8 = ({{R[[1, 8]], R[[2, 8]], R[[3, 8]], R[[4, 8]],
R[[5, 8]], R[[6, 8]],
R[[7, 8]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1, 3]]}, {VaR[[
1, 4]]}, {VaR[[1, 5]]}, {VaR[[1, 6]]}, {VaR[[1,
7]]}})/\[Sqrt]({{VaR[[1, 1]], VaR[[1, 2]], VaR[[1, 3]],
VaR[[1, 4]], VaR[[1, 5]], VaR[[1, 6]],
VaR[[1, 7]]}}.{{R[[1, 1]], R[[1, 2]], R[[1, 3]], R[[1, 4]],
R[[1, 5]], R[[1, 6]], R[[1, 7]]}, {R[[2, 1]], R[[2, 2]],
R[[2, 3]], R[[2, 4]], R[[2, 5]], R[[2, 6]],
R[[2, 7]]}, {R[[3, 1]], R[[3, 2]], R[[3, 3]], R[[3, 4]],
R[[3, 5]], R[[3, 6]], R[[3, 7]]}, {R[[4, 1]], R[[4, 2]],
R[[4, 3]], R[[4, 4]], R[[4, 5]], R[[4, 6]],
R[[4, 7]]}, {R[[5, 1]], R[[5, 2]], R[[5, 3]], R[[5, 4]],
R[[5, 5]], R[[5, 6]], R[[5, 7]]}, {R[[6, 1]], R[[6, 2]],
R[[6, 3]], R[[6, 4]], R[[6, 5]], R[[6, 6]],
R[[6, 7]]}, {R[[7, 1]], R[[7, 2]], R[[7, 3]], R[[7, 4]],
R[[7, 5]], R[[7, 6]],
R[[7, 7]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1,
3]]}, {VaR[[1, 4]]}, {VaR[[1, 5]]}, {VaR[[1, 6]]}, {VaR[[1,
7]]}})
{{0.545535}}
korrelation1234678zu9 = ({{R[[1, 9]], R[[2, 9]], R[[3, 9]], R[[4, 9]],
R[[5, 9]], R[[6, 9]], R[[7, 9]],
R[[8, 9]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1, 3]]}, {VaR[[
1, 4]]}, {VaR[[1, 5]]}, {VaR[[1, 6]]}, {VaR[[1, 7]]}, {VaR[[1,
8]]}})/\[Sqrt]({{VaR[[1, 1]], VaR[[1, 2]], VaR[[1, 3]],
VaR[[1, 4]], VaR[[1, 5]], VaR[[1, 6]], VaR[[1, 7]],
VaR[[1, 8]]}}.{{R[[1, 1]], R[[1, 2]], R[[1, 3]], R[[1, 4]],
R[[1, 5]], R[[1, 6]], R[[1, 7]], R[[1, 8]]}, {R[[2, 1]],
R[[2, 2]], R[[2, 3]], R[[2, 4]], R[[2, 5]], R[[2, 6]],
R[[2, 7]], R[[2, 8]]}, {R[[3, 1]], R[[3, 2]], R[[3, 3]],
R[[3, 4]], R[[3, 5]], R[[3, 6]], R[[3, 7]],
R[[3, 8]]}, {R[[4, 1]], R[[4, 2]], R[[4, 3]], R[[4, 4]],
R[[4, 5]], R[[4, 6]], R[[4, 7]], R[[4, 8]]}, {R[[5, 1]],
R[[5, 2]], R[[5, 3]], R[[5, 4]], R[[5, 5]], R[[5, 6]],
R[[5, 7]], R[[5, 8]]}, {R[[6, 1]], R[[6, 2]], R[[6, 3]],
R[[6, 4]], R[[6, 5]], R[[6, 6]], R[[6, 7]],
R[[6, 8]]}, {R[[7, 1]], R[[7, 2]], R[[7, 3]], R[[7, 4]],
R[[7, 5]], R[[7, 6]], R[[7, 7]], R[[7, 8]]}, {R[[8, 1]],
R[[8, 2]], R[[8, 3]], R[[8, 4]], R[[8, 5]], R[[8, 6]],
R[[8, 7]],
R[[8, 8]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1,
3]]}, {VaR[[1, 4]]}, {VaR[[1, 5]]}, {VaR[[1, 6]]}, {VaR[[1,
7]]}, {VaR[[1, 8]]}})
{{0.233015}}
korrelation12346789zu10 = ({{R[[1, 10]], R[[2, 10]], R[[3, 10]],
R[[4, 10]], R[[5, 10]], R[[6, 10]], R[[7, 10]], R[[8, 10]],
R[[9, 10]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1,
3]]}, {VaR[[1, 4]]}, {VaR[[1, 5]]}, {VaR[[1, 6]]}, {VaR[[1,
7]]}, {VaR[[1, 8]]}, {VaR[[1, 9]]}})/\[Sqrt]({{VaR[[1, 1]],
VaR[[1, 2]], VaR[[1, 3]], VaR[[1, 4]], VaR[[1, 5]],
VaR[[1, 6]], VaR[[1, 7]], VaR[[1, 8]],
VaR[[1, 9]]}}.{{R[[1, 1]], R[[1, 2]], R[[1, 3]], R[[1, 4]],
R[[1, 5]], R[[1, 6]], R[[1, 7]], R[[1, 8]],
R[[1, 9]]}, {R[[2, 1]], R[[2, 2]], R[[2, 3]], R[[2, 4]],
R[[2, 5]], R[[2, 6]], R[[2, 7]], R[[2, 8]],
R[[2, 9]]}, {R[[3, 1]], R[[3, 2]], R[[3, 3]], R[[3, 4]],
R[[3, 5]], R[[3, 6]], R[[3, 7]], R[[3, 8]],
R[[3, 9]]}, {R[[4, 1]], R[[4, 2]], R[[4, 3]], R[[4, 4]],
R[[4, 5]], R[[4, 6]], R[[4, 7]], R[[4, 8]],
R[[4, 9]]}, {R[[5, 1]], R[[5, 2]], R[[5, 3]], R[[5, 4]],
R[[5, 5]], R[[5, 6]], R[[5, 7]], R[[5, 8]],
R[[5, 9]]}, {R[[6, 1]], R[[6, 2]], R[[6, 3]], R[[6, 4]],
R[[6, 5]], R[[6, 6]], R[[6, 7]], R[[6, 8]],
R[[6, 9]]}, {R[[7, 1]], R[[7, 2]], R[[7, 3]], R[[7, 4]],
R[[7, 5]], R[[7, 6]], R[[7, 7]], R[[7, 8]],
R[[7, 9]]}, {R[[8, 1]], R[[8, 2]], R[[8, 3]], R[[8, 4]],
R[[8, 5]], R[[8, 6]], R[[8, 7]], R[[8, 8]],
R[[8, 9]]}, {R[[9, 1]], R[[9, 2]], R[[9, 3]], R[[9, 4]],
R[[9, 5]], R[[9, 6]], R[[9, 7]], R[[9, 8]],
R[[9, 9]]}}.{{VaR[[1, 1]]}, {VaR[[1, 2]]}, {VaR[[1,
3]]}, {VaR[[1, 4]]}, {VaR[[1, 5]]}, {VaR[[1, 6]]}, {VaR[[1,
7]]}, {VaR[[1, 8]]}, {VaR[[1, 9]]}})
{{0.337219}}
i hope anybody have an advice for me. thx
Attachments: