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OCR S1 Spearman's rank correlation coefficient help please watch

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    I've attached the picture of the question from June 2014.
    For part i) I know the answer is 6 5 4 3 2 1 but I'm unsure why.
    For part ii) I worked out the sum of  d^2  of the 2 teams as 2. For the 6 teams the sum of  d^2  is 70. However the mark scheme said for the 6 teams, it's 0. I don't understand how they got the answer.
    My SRCC answer is also wrong. I got 1/7 instead of 41/42.
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    (Original post by osayuki)
    I've attached the picture of the question from June 2014.
    For part i) I know the answer is 6 5 4 3 2 1 but I'm unsure why.
    For part ii) I worked out the sum of  d^2  of the 2 teams as 2. For the 6 teams the sum of  d^2  is 70. However the mark scheme said for the 6 teams, it's 0. I don't understand how they got the answer.
    My SRCC answer is also wrong. I got 1/7 instead of 41/42.
    i) If r_s = -1 it means there is perfect negative linear correlation, ie. the rankings are the exact opposite in one set to the other. Basically, they're in the same order but backwards, if that makes sense?
    ii) Are you using the new information given? Seems to me like you're calculating d^2 for the table given in the previous part, instead of using the new value of r_s = 1. Can you see why d^2 = 0 from there?
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    (Original post by tinkerbella~;[url="tel:62756003")
    62756003[/url]]i) If r_s = -1 it means there is perfect negative linear correlation, ie. the rankings are the exact opposite in one set to the other. Basically, they're in the same order but backwards, if that makes sense?
    ii) Are you using the new information given? Seems to me like you're calculating d^2 for the table given in the previous part, instead of using the new value of r_s = 1. Can you see why d^2 = 0 from there?
    Thank you so much, I'll solve it after I eat.
 
 
 
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