Ch.10 Summarizing Data 10.2 Methods based on the C.D.F
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Transcript of Ch.10 Summarizing Data 10.2 Methods based on the C.D.F
10.2 10.3
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Ch.10 Summarizing Data
10.2 Methods based on the C.D.F
10.2 10.3
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10.2 10.3
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10.2 10.3
Eg: Guinea pig 接種不同劑量的結核菌 (tubercle bacilli)
Control group(107 隻 )
Inoculated group ⅠⅡⅢⅣⅤ 各 72 隻 , 按照劑量順序排列 表 10.2.1
表 10.2.2
在 Control group 及較低量的注射劑群並非所有的天竺鼠都死,因此在 Control group 中只有 65筆 data,在 DoseⅠ及 DoseⅡ 分別都只有 60,67筆 data
目的:比較對不同抵抗力的天竺鼠,其增加注射劑量的效果差別!Eg :對 Group Ⅲ 及Ⅳ (1) 對抵抗力較弱的天竺鼠 ( 其生命中 10% weakest ,即在圖中的 y 軸畫 0.9 的水平線其所對應的 x 軸,即為此 10% weakest 的最長生命期 )
Group Ⅲ 及Ⅳ的差距約在 50 天 (2) 然而對抵抗力較強的天竺鼠, Group Ⅲ 及Ⅳ的差距大約在 100 天左右
10.2 10.3
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10.2 10.3
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10.2 10.3
Eg :天竺鼠的例子(1) 一開始的 hazard function 在每個 group 中都很小
(2) 隨著注射劑量的增加,其瞬時死亡率不僅增加且其增加的速率也隨著劑量的增加而加快
E.g.Ⅲ及Ⅴ的比較,Ⅴ較Ⅲ其 instant mortality rate 增加的速率較 快,且最後其曲線所相對的斜率也較Ⅲ的相對斜率更大 Figure10.2
10.2 10.3
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10.2 10.3
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10.2 10.3
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10.2 10.3
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10.2 10.3
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10.2 10.3
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10.2 10.3
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