3,303
edits
Changes
Jump to navigation
Jump to search
Line 3:
Line 3: − + − − ''See end of this article to understand 'Not' in the above.'' [[User:DavyJones|DavyJones]] 17:12, 17 October 2008 (EDT) Line 164:
Line 162: − === ''Not'' confirmed === − − Like Kennymac and Longstop, I have some qualifications in this area because I have taught statistics to researchers (not mathematicians) - actually for even longer than Kennymac. I've read the contribution from Longstop and I've decided that the best thing I can do is to replace it in its entirety because it makes the point quite well. (Actually both points - the statistical point and the one about reviewing scientific papers.) But my qualifications are really unimportant - as Longstop said, it doesn't matter who says something in science, it's '''what''' they say that matters. After all, the most important discoveries in science in the 20th century were made by a patent clerk who wasn't an academic at the time and hadn't even been a particularly outstanding student. − − The rest of this posting is cut-and-pasted from Longstop's contribution earlier this week. − − The main point he [Kennymac] makes is quite correct, that combining experiments will tend to give a more significant result (i.e. a lower P-value) than any single experiment on its own. − − The point that ASchlafly makes (headed '''REPLY''', shortly after KennyMac's example) is slightly misleading. You don't choose which experiments to combine on the basis of their outcomes - you either combine all relevant experiments or none. In this case, Professor Lenski chose to combine all the experiments and present a single analysis of them. That's fine. − − The issue of whether to weight the Z-test according to sample size is not a straightforward issue. Before Whitlock's recent paper, the consensus was that the P-value already depends on sample size so it should not be weighted according to sample size. (Basically, a high degree of significance, i.e. a low P-value, can be achieved by having either a large difference between the treatments or a large experiment or, of course, both.) Whitlock's work, based on computer simulations, is an interesting contribution but cannot be regarded as the last word on the subject because any computer simulation involves assumptions about the structure of the particular experiment simulated. I cannot imagine any editor of a scientific journal rejecting a paper because it used an unweighted Z-test rather than the weighted version (or vice-versa). − − The conclusion, therefore, is that while there is a quantitative difference in the level of significance obtained by weighted and unweighted Z-tests, there is undeniably a significant biological effect. ASchlafly and other contributors should not be concerned that there is anything incorrect about the biological conclusions of Professor Lenski and his students or that there was anything at all underhand about their analysis or presentation of their data. − On a different point, please would CP readers note that there's nothing at all suspicious about a paper being peer-reviewed in only 14 days. Editors of scientific journals ask reviewers beforehand if they are free to edit a paper within a certain period of time. If an academic agrees to review a paper for a prestigious journal such as PNAS within 2 weeks, they will generally ensure they have time during that period to read and comment on the paper thoroughly. [[User:DavyJones|DavyJones]] 17:12, 17 October 2008 (EDT)
Talk:PNAS Response to Letter (view source)
Revision as of 21:17, October 17, 2008
, 21:17, October 17, 2008Undo revision 538020 by DavyJones (Talk)
Note: earlier posts are archived [[Talk:PNAS_Response_to_Letter/Archive1|here]]. --[[User:BillA|BillA]] 17:05, 20 September 2008 (EDT)
Note: earlier posts are archived [[Talk:PNAS_Response_to_Letter/Archive1|here]]. --[[User:BillA|BillA]] 17:05, 20 September 2008 (EDT)
== Point 5 Not Confirmed ==
== Point 5 Confirmed ==
I would like to contribute to this discussion because I have taught statistics to graduate biology students for 16 years.
I would like to contribute to this discussion because I have taught statistics to graduate biology students for 16 years.
Maybe the Journal of Nature can be your next letter submission source. ''International Weekly Journal of Science'' -- [[Image:50 star flag.png|14px]] [[User:Jpatt|jp]] 21:17, 22 September 2008 (EDT)
Maybe the Journal of Nature can be your next letter submission source. ''International Weekly Journal of Science'' -- [[Image:50 star flag.png|14px]] [[User:Jpatt|jp]] 21:17, 22 September 2008 (EDT)
== References ==
== References ==
<references/>
<references/>