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# Biology statistics - degrees of freedom watch

1. In both questions that I attached, the number of pairs of data was 10.

For the spearmans rank correlation question, the critical values were taken at n = 10 (so 0.648 and 0.794).

However for the pearsons linear correlation question, the critical value was measured at n = 8. So even though the heading column was number of pairs of data, we still use degrees of freedom

My question is, when do we used the number of pairs data and when do we use degrees of freedom?

I would really appreciate any help.
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3. (Original post by Keira Larkin)
(...)

My question is, when do we used the number of pairs data and when do we use degrees of freedom?

I would really appreciate any help.
Hi! First of all thanks that you have contacted me. I would love to know why did you have choose me. By all means, back to your question:

As far as I can see pairs of data is a sample and this is used in mathematics to have a sufficient number to make a safe statement in statistics, the greater the number, the safer the statement. So for pairs of data it is important that the number is not too small to doubt the investigation and not too big to make too much effort.

The degree of freedom is a value which allows a variation between different calulcated values. In short: it is a value for a valid difference. This unit in mathematics is used and calculated to check the validity of an investigation when it comes to variations.

I will write a report to a staff that it will be moved to mathematics.
4. (Original post by Kallisto)
Hi! First of all thanks that you have contacted me. I would love to know why did you have choose me. By all means, back to your question:

As far as I can see pairs of data is a sample and this is used in mathematics to have a sufficient number to make a safe statement in statistics, the greater the number, the safer the statement. So for pairs of data it is important that the number is not too small to doubt the investigation and not too big to make too much effort.

The degree of freedom is a value which allows a variation between different calulcated values. In short: it is a value for a valid difference. This unit in mathematics is used and calculated to check the validity of an investigation when it comes to variations.

I will write a report to a staff that it will be moved to mathematics.
Thank you so much for replying! I sent you a PM because you had answered one of my questions in biology before.

So are you saying that pairs of data is used when you have the same number of observations in each category but degrees of freedom is for different numbers of observations?
5. (Original post by Keira Larkin)
Thank you so much for replying! I sent you a PM because you had answered one of my questions in biology before.

So are you saying that pairs of data is used when you have the same number of observations in each category but degrees of freedom is for different numbers of observations?
Oh, now you said this to me, I remember your name. True, I have helped you and offered my help, if you are in trouble again, right?

If pairs of data means to be a sample for statistics, it is a fixed number for observations. A number which is determined before observations. As far as I understand, degree of freedom is dependend on the sample n.

I am a bit confused with those terms. That is why I can't give you a clear answer at 100%.

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Updated: March 13, 2018
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