The ratings of 6 laptops in two websites A and B are given below. Find the rank coefficient for the ratings of the two websites.
LaptopsABL178L28.59.5L39.58L488L58.56.5L67.57.5
0.114
Convert the ratings to the corresponding ranks and calculate the deviations.
LaptopsABDi=A−BD2iL16339L22.511.52.25L313−24L44311L52.56−3.512.25L65500∑=28.5
The rank 2.5 is repeating 2 times for A and the rank 3 is repeating 3 times for B
∴m1=2m2=3
rk=1−6[∑D2i+m31−m112+m32−m212+…]n3−n
=1−6×(28.5+0.5+2)216−6=1−186210=0.114