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    Found last part to be 18.2 and then I tried to use linear interpolation but it didn't seem to work :/

    Attachment 527695527699

    I get that Syy rises, but why doesn't Sxy rise if y rises?

    (only need a hand on the last part of each question)
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    (Original post by creativebuzz)
    I get that Syy rises, but why doesn't Sxy rise if y rises?
    Because if the change in y is negated by the change in \bar{y} and hence this means that the y - \bar{y} term in the summation doesn't really change when summed over, and hence S_{xy} doesn't change.
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    (Original post by Zacken)
    Because if the change in y is negated by the change in \bar{y} .
    But Syy increases so surely the change in y is not negated by the change is y bar
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    (Original post by Zacken)
    Because if the change in y is negated by the change in \bar{y} and hence this means that the y - \bar{y} term in the summation doesn't really change when summed over, and hence S_{xy} doesn't change.
    Sorry to be so annoying but would you mind explaining?
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    (Original post by creativebuzz)
    Sorry to be so annoying but would you mind explaining?
    for the new name, x-xbar is 0, meaning Sxy doesn't change because when multiplying x-xbar by y-ybar for the new name, you get zero so the overall sum remains unchanged
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    (Original post by veejn)
    for the new name, x-xbar is 0, meaning Sxy doesn't change because when multiplying x-xbar by y-ybar for the new name, you get zero so the overall sum remains unchanged
    Ohhh now I understand, thanks!

    Would you mind giving me a hand on the first picture I posted in the first post of this thread? (I only need help on the last part of that question) (the tomato one)
 
 
 
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