[{"data":1,"prerenderedAt":-1},["ShallowReactive",2],{"$f3MlBTwxKy0WXlhJQA0J9M5EBnIN3HKYktvz6C0LQV5g":3},{"answer":4,"createTime":5,"id":6,"options":7,"origin":12,"question":19,"related":20,"source":30,"type":62},[],"2024-01-09 15:58:28",129610154,[8,9,10,11],"两个总体方差均未知,样本1容量=40,样本2容量=20","两个总体方差均已知,样本1容量=15,样本2容量=20","两个总体方差均未知,样本1容量=30,样本2容量=30","总体1方差已知,总体2方差未知,样本1容量=20,样本2容量=30",{"count":13,"courseId":14,"courseImg":15,"courseName":16,"workId":17,"workName":18},8,"0db2a93448a4c2b6e40657f4cea0eeed","https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F325e975e21088405054ac8cc902706af.png","2023－2024－1生技试验设计与统计分析","aa5d4a6ee64e40f8acef52becc43f0b1","4.2.2 测验","在两个成组数据的样本平均数的假设检验中,应当采用u检验的是( )",[21,32,41,50,59,63,71,80],{"answer":22,"createTime":5,"id":23,"options":24,"question":29,"source":30,"type":31},[],129610150,[25,26,27,28],"两个总体方差均未知但经F检验发现这两者方差相等时,此时t值的自由度为n1+n2-1","两个总体方差均未知但经F检验发现这两者方差不相等,且样本1与样本2的大小也不相等时,t值的自由度为n1+n2-2","两个总体方差均未知但经F检验发现这两者方差不相等,但样本1与样本2的大小相等时,t值的自由度为2n-2","两个总体方差均未知但经F检验发现这两者方差不相等,但样本1与样本2的大小相等时,t值的自由度为n-1","关于两个样本平均数的 t 检验下列说法正确的是( )","v1",0,{"answer":33,"createTime":5,"id":34,"options":35,"question":40,"source":30,"type":31},[],129610151,[36,37,38,39],"采用u检验,u=1.91,没有显著差异","采用u检验,u= -4.551,存在极显著差异","采用t检验,t=1.56,没有显著差异","采用t检验,t= -3.23,存在极显著差异","检查三化螟各世代每卵块的卵数,检查第一代128个卵块,其平均数为47.3粒,标准为24.5粒;检查第二代69个卵块,其平均数为74.9粒,标准差为46.8粒.试检验两代每卵块的卵数有无显著差异,则( )",{"answer":42,"createTime":5,"id":43,"options":44,"question":49,"source":30,"type":31},[],129610152,[45,46,47,48],"F=1.834,总体方差不同质,t = -1.56,没有显著差异","F=1.834,总体方差同质,t = -0.147,没有显著差异","F=3.65,总体方差不同质,t= -1.56,存在显著差异","F=3.65,总体方差同质,t= -0.147,存在显著差异","为了验证"北方动物比南方动物具有较短的附肢"这一假说,调查了如下鸟翅长资料.北方的鸟翅长为:120, 113, 125, 118, 116, 114, 119;南方的鸟翅长为116, 117, 121, 114, 116, 118, 123, 120,试检验这一假说,则( )",{"answer":51,"createTime":5,"id":52,"options":53,"question":58,"source":30,"type":31},[],129610153,[54,55,56,57],"成组数据t检验,t=1.012,P>0.05,不具有降血压作用","成对数据t检验,t=2.253,P<0.05,具有显著降血压作用","成对数据t检验,t=1.012,P>0.05,不具有降血压作用","成对数据t检验,t=5.701,P<0.01,具有极显著降血压作用","用中草药青木香治疗高血压,记录了13个病例,所测得的舒张压(mmHg)数据如下表所示,问该药是否有降血压的作用. \u003Cimg src=\"https:\u002F\u002Ftihai-oss-cloud.itihey.com\u002Fimg\u002F42388ddb9765303a4ccd1718703308b0.png\">",{"answer":60,"createTime":5,"id":6,"options":61,"question":19,"source":30,"type":62},[],[8,9,10,11],1,{"answer":64,"createTime":5,"id":65,"options":66,"question":70,"source":30,"type":62},[],129610155,[67,68,69,8],"两个总体方差均已知,样本1容量=20,样本2容量=15","两个总体方差均未知,样本1容量=30,样本2容量=40","两个总体方差均未知,样本1容量=20,样本2容量=15","在两个成组数据的样本平均数的假设检验中,应当采用t检验的是( )",{"answer":72,"createTime":73,"id":74,"options":75,"question":78,"source":30,"type":79},[],"2025-11-07 03:20:46",229990542,[76,77],"正确","错误","当两个样本大小相等时,应采用成对数据的t检验以提高检验灵敏度",3,{"answer":81,"createTime":73,"id":82,"options":83,"question":84,"source":30,"type":79},[],229990543,[76,77],"在试验研究中,为加强某些试验条件的控制,做成成对数据比成组数据效果更好"]