Talk:Permutation test: Difference between revisions

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(comments on numerical stability)
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--[[User:Sluggo|Sluggo]] 02:06, 4 February 2011 (UTC)
--[[User:Sluggo|Sluggo]] 02:06, 4 February 2011 (UTC)


===Using rational arithmatic===
===Using rational arithmetic===
I wondered about the accuracy of results after it was queried above and ran the Python solution but with rational numbers as input to see what effect this may have.
I wondered about the accuracy of results after it was queried above and ran the Python solution but with rational numbers as input to see what effect this may have.


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:::Actually, I was asking about how the large and small value reversed (between the under and over categories) in those two cases. --[[User:Rdm|Rdm]] 17:14, 4 February 2011 (UTC)
:::Actually, I was asking about how the large and small value reversed (between the under and over categories) in those two cases. --[[User:Rdm|Rdm]] 17:14, 4 February 2011 (UTC)
===Using integer arithmetic ===

Rationals are a bit of overkill when the denominator is always the same. I just posted a version using all integer arithmetic. The problem with floats is those 313 cases where the differences are equal. Anything that causes the difference to be off by the tiniest bit can cause them to be mis-categorized. I don't know enough statistics to know how this is typically handled. For this task, it might be enough to change the task description to provide experimental results as an integer score from 0 to 100. While we're at it, we could change the task to specify that the difference is treatment-control. That would eliminate the double solution.—[[User:Sonia|Sonia]] 20:12, 4 February 2011 (UTC)
== Name of task ==
== Name of task ==
Shouldn't this be all combinations instead of all permutations? What difference does the order of members within the control or treatment group make (other than extra computation time)? --[[User:Rdm|Rdm]] 16:08, 1 February 2011 (UTC)
Shouldn't this be all combinations instead of all permutations? What difference does the order of members within the control or treatment group make (other than extra computation time)? --[[User:Rdm|Rdm]] 16:08, 1 February 2011 (UTC)