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

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?

Reply 1

Adorable98

Bump!! Bump!! Bump!! :smile:

Bump!! Bump!! Bump!!

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

Reply 4

Adorable98

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