# How do you choose the "critical value" from the table?[ Rank Correlation Coefficient]

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1. So I know you choose the 5% Column, but which one is the critical value?

Here's an example:
A student observed that the yield of oranges increased as the abundance of honeybee hives in the orange hives increased. She counted the number of hives in different groves and then measured the yield in each grove. She decided to determine whether there was any association between the two variables.

Grove no |No. of honeybee hives/ grove |Yield of Oranges in tonnes/ grove
1 | 122 | 107
2 | 66 | 32
3 | 79 | 61
4 | 94 | 111
5 | 43 | 48
6 | 64 | 72
7 | 30 | 34
8 | 91 | 76
9 | 110 | 119
10 | 76 | 90
11 | 61 | 90
12 | 104 | 59
13 | 67 | 64
14 | 30 | 46
15 | 92 | 90

Critical value

n/p | 0.05
-- | --
-- | --
-- | --
28 | 0.3739
29 | 0.3673
30 | 0.3610

So the calculated value is(0.68125).
But the Critical value is (0.361) ? Why's that?
2. Bump!! Bump!! Bump!!
3. Bump!! Bump!! Bump!!
4. Don't you have 15 pairs of data?

And yeah, the calculated value can be greater/less than the critical value. That's how you know if the correlation is significant
5. (Original post by Serine Soul)
Don't you have 15 pairs of data?
And yeah, the calculated value can be greater/less than the critical value. That's how you know if the correlation is significant
Yes! but why didn't they choose n/p = 15?
6. (Original post by Adorable98)
Yes! but why didn't they choose n/p = 15?
No idea, is this a textbook example?

Have another look at an example online
7. (Original post by Adorable98)
Yes! but why didn't they choose n/p = 15?
Should be 15

Posted from TSR Mobile
8. (Original post by Serine Soul)
No idea, is this a textbook example?

Have another look at an example online
(Original post by Asklepios)
Should be 15

Posted from TSR Mobile
it's from a textbook I bought online.
I see, thanks!

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