The product of partial regression coefficient \(b_1{_2}{_.3}\)\(b_2{_3}{_.1}\)\(b_3{_1}{_.2}\) equals to:
1
\(\dfrac{r_1{_2}{_.3}+r_2{_3}{_.1}+r_3{_1}{_.2}}{3}\)
2
\((r_1{_2}{_.3}r_2{_3}{_.1}r_3{_1}{_.2})^\dfrac{1}{2}\)
3
\(\dfrac{1}{r_1{_2}{_.3}} + \dfrac{1}{r_2{_3{_.1}}} + \dfrac{1}{r_3{_1}{_.2}}\)
4
\(r_1{_2}{_.3}r_2{_3}{_.1}r_3{_1}{_.2}\)