CED,
Degrees of freedom is the term used to eliminate bias in your data.
Bias is the term used when you can foretell the data(number) you want to collect.
to illustrate:
If you have four golf balls numbered with 1, 2, 3, and 4 in a basket. One of these balls will be randomly taken out ( n-1 ) and you will be left with three balls to pick in the basket. You don’t know what number was taken out so, you cannot tell what are the three numbers left.
1. Before you pick the first ball, can you tell me the number you will get? Of course not because numbers 1, 2, 3, and 4 have the same probability of being picked. 1/4 ( ohh! it’s number 3, keep the number 3 ball )
2. before you pick the second ball, can you tell me the number you will get? Again, you can’t because numbers 1, 2, and 4 have the same probability to be picked. 1/3 ( ohh! I got number 1, keep the number 1 ball )
So, you already have number 1 and 3 and there’s only one ball in the basket, can you tell me what number is that remaining ball? Nope, you can’t because of ( n-1 ). the remaining ball can be 2 or 4 with the same probability to be picked- 1/2.
hope this helps.
AbetF
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