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Talk:Significance of E. Coli Evolution Experiments (view source)
Revision as of 02:25, March 19, 2009
, 02:25, March 19, 2009→Misinterpretation of test
The article also continues to describe 'mean mutation generation' as a ''test'' rather than a ''statistic'' to which the ''Monte Carlo test'' was applied.--[[User:ElyM|ElyM]] 17:24, 14 March 2009 (EDT)
The article also continues to describe 'mean mutation generation' as a ''test'' rather than a ''statistic'' to which the ''Monte Carlo test'' was applied.--[[User:ElyM|ElyM]] 17:24, 14 March 2009 (EDT)
I'm a bit confused about why the Chi-squared test, which we're told compares the results to a null hypothesis of a constant mutation rate, seems insensitive to which generations the Cit+ mutations are found. Instead, the chi-square test seems only to be evaluating whether the frequencies of Cit+ mutations in any particular generation are 'expected'. Thus the test is asking whether finding a distribution (e.g. in the first experiment) across nine periods that have no mutations, two periods that have one mutation and one period with two mutations is a statistically significant deviation from what you'd expect of the mutations were randomly distributed. The number returned from the function is the same regardless of the order of Cit+ results. The number of mutations per bin is not the only question being asked. Instead it's the '''order and temporal distribution''' of Cit+ mutants that the analyses probably need to confront. It's not whether one can get nine no-mutants, two single mutants and one double-mutant result, it's a matter of '''when''' they occur and whether that distribution affects the significance of the results. Blount's hypothesis is that mutations should appear later in the experiment. When formulating a suitable null hypothesis, wouldn't one want to take the timing of Cit+ mutants into consideration too?--[[User:Argon|Argon]] 22:25, 18 March 2009 (EDT)
==Unreferenced Claims==
==Unreferenced Claims==