Question

Anyone know Spearman's Rank correclation coefficient? I need help with a problem...

Answer 1

Refer this it might be helpful
http://en.wikipedia.org/wiki/Spearman%27s_rank_correlation_coefficient

Answer 2

I know that it's \[\rho = 1- {\frac {6 \sum d_i^2}{n(n^2 - 1)}}. \]

But I'm solving an equation... and the answer at the back of the book isn't the same as my answer, as long as I've been trying it, and I don't know what I'm doing wrong... so I was wondering if anyone was familiar with it to see if they got the same answer as that of the back of the book?

Answer 3

What are the details? Do you have x and y values?

Answer 4

Yes, I can give them if you know how to use it...

Answer 5

rs=1-6summitionDsquare/ncube-n

Answer 6

Ph k sry then give the details and I will try my best

Answer 7

Magazine 1: 13 20 22 18 19 11 10 15
Magazine 2: 17 19 23 16 20 10 11 18

Answer 8

First sort the 2 sequences, and number them 1..N

Answer 9

dind uot difference

Answer 10

and then do the square of the difference

Answer 11

Yes, That's what I thought. What do you mean by sorting? Aren't they already sorted?

Answer 12

here n=8

Answer 13

assign them rank

Answer 14

how do you assign them rank?

Answer 15

m1 10, 11, 13, 15, 18, 19, 20, 22
1 2 3 4 5 6 7 8
m2 10, 11, 16, 17, 18, 19, 20, 23
1 2 3 4 5 6 7 8


Magazine 1: 13 20 22 18 19 11 10 15
3 7 8 4 5 2 1 3
Magazine 2: 17 19 23 16 20 10 11 18
3 5 8 3 6 1 2 4

Answer 16

Sorted mag 1's numbers, and assigned it 1,2,3 ... from small to large. Used these to label the original sequence.

Answer 17

now subtract the ranks to get the d's

Answer 18

Magazine 1: 13 20 22 18 19 11 10 15
3 7 8 4 5 2 1 3
Magazine 2: 17 19 23 16 20 10 11 18
3 5 8 3 6 1 2 4


d's 0 2 0 1 -1 1 -1 -1
d sq 0 4 0 1 1 1 1 1

Answer 19

How did you get that? I mean the d's

Answer 20

First, I labeled the 13 of mag 1 with its rank (3, which is its order if you sorted mag 1's numbers). I labeled mag 2's 17 with a 3 (its rank)
d= 3-3= 0
ditto for the rest...

Answer 21

I thought 17 was 4? You don't have a 7 in your ranking in magazine 2..?

Answer 22

Yes, you are right... Feel free to fix up my mistakes.

Answer 23

Ok... If I get the answer now, I'll tell you...

Answer 24

I got it :) Thanks!

Answer 25

If I didn't make any mistakes

Magazine 1: 13 20 22 18 19 11 10 15
3 7 8 5 6 2 1 4
Magazine 2: 17 19 23 16 20 10 11 18
4 6 8 3 7 1 2 5


d's -1 -1 0 2 -1 1 -1 -1
d sq 1 1 0 4 1 1 1 1

Answer 26

Yes that's right!

Answer 27

So the coeff is about 0.88