80 



BELL SYSTEM TECHNICAL JOURNAL 



X1X2. = lol's = X w(/n)A/27r(/„ — fm) = ^1 



1 



«4^5 = hic = —bi 



N 



'cc^, = Icic = -L^^(/)A/'47r'(/„ -fmY = -62 

 1 



X4X6 = Igls = "^2 



0C2XZ = Isle = —bz 



X^Xf, = Icis = bz 



All of the other second moments are zero. 



The moment matrix M is thus 



(3.8-3) 



B = bobibi -\- 2 bib2bz 



— 62 — bobz — bibi 



I M I = 5' 



where B is the determinant of the third order matrices in the upper left and 

 lower right corners of^M. 



jjjAs in the earlier work, the distribution oi Xi , • • - , Xe is normal in six 

 dimensions. The exponent is — [2 j M | ]~ times 



Bo{xi + Xi) + 25i(xiX2 — XiXi) — IBiixiXi + XiX^) 



+ -622(^1^2 + Xi) — 2B3{X2Xz — XaXo) (3.8-4) 



+ Bi{xl + xl) 



