问大侠们个Significant Difference Testing问题

什么原因可造成下列结果

二组email list，test vs control，statistical test结果是significant difference，但实际上不是

所有跟帖： 

• the difference might be introduced by confounders -veggiedoggie- ♀ (84 bytes) () 06/26/2012 postreply 17:22:16

• 回复：the difference might be introduced by confounders -silymind- ♀ (110 bytes) () 06/26/2012 postreply 17:37:53

• to identify confounders, there might be several ways -veggiedoggie- ♀ (724 bytes) () 06/26/2012 postreply 18:32:55

• 回复：to identify confounders, there might be several ways -silymind- ♀ (61 bytes) () 06/26/2012 postreply 19:35:19

• this is the definition of Type I error, or false positive. googl -Kamioka- ♀ (442 bytes) () 06/26/2012 postreply 19:35:28

• as to how it could happened it your specific study, first check -Kamioka- ♀ (2338 bytes) () 06/26/2012 postreply 20:15:34

• 你问的问题 -iwww- ♀ (18560 bytes) () 06/27/2012 postreply 08:24:07

• yes, whether the detected difference is truly there and whether -Kamioka- ♀ (831 bytes) () 06/27/2012 postreply 10:49:25

• Thanks everyone! So many smart 大侠 here :-) -silymind- ♀ (0 bytes) () 06/27/2012 postreply 12:56:09

• What is the variable you try to test? -小谋- ♀ (0 bytes) () 06/27/2012 postreply 17:19:29

• 回复：What is the variable you try to test? -silymind- ♀ (54 bytes) () 06/27/2012 postreply 21:40:53