两组呈正态分布的数值变量资料，但均数相差很大，若比较离散趋势，最好选用的指标为

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29809' and id < 2419257 and id<>'2419257' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29809' and id > 2419257 and id<>'2419257' order by id asc limit 5