求标准正态z统计量对应于x拔=15.5的值 这个问题什么意思？给个思路
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\u987a\u795d\u597d\u8fd0\uff01
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其实统计量就是X拔=15.5对应在标准正态分布的一个量。即对应的值为m=（X拔-均值）/样本标准差
其中样本标准差=总体标准差/样本总量的开二次方
绛旓細) 鍙堝洜涓篨1路路路Xn鏈嶄粠鏍囧噯姝ｆ鍒嗗竷 鎵浠锛圶1²锛=鈭紙涓婁笅闄愬垎鍒负卤鈭烇級锛x²f锛坸锛塪x 銆恌(x)鏄爣鍑嗘鎬佸垎甯冪殑姒傜巼瀵嗗害鍑芥暟銆戠劧鍚庢妸杩欎釜绉垎姹傚嚭鍙互寰桬(X1²)=1 鎵浠(X)=E(X1²)+E(X2²)+E(X3²)+路路路E(Xn²)=n ...
绛旓細鍥犱负P{Z<1.96}=1-0.025=0.975銆傚嵆闇瑕佹煡1-0.025=0.975瀵瑰簲鐨刏鍊硷紝缈诲紑姝ｆ鍒嗗竷琛紝鍒氬ソ鑳芥煡鍒0.9750瀵瑰簲鐨刏鍊间负1.96锛屾晠Z0.025=1.96銆備綘瑕佸弽鐫鏌ワ紝浠庨偅涓鐗囨暟閲屾壘0.975锛屽搴旂殑鏄1.96銆
绛旓細鍙嶇潃鏌ャ備緥濡傦細98%鐨勭疆淇″尯闂寸畻Z锛1-0.98=0.02锛0.02/2=0.01; 1-0.01=0.9900锛涙煡姝ｆ鍒嗗竷琛紝鍦ㄩ偅涓鍫嗗洓浣嶅皬鏁扮殑鍊奸噷鎵惧埌涓0.9900鏈鎺ヨ繎鐨勫硷紝姣斿0.9901瀵瑰簲鐨勬槸2.33锛屾墍浠98%瀵瑰簲鐨Z缁熻閲鏄2.33鎴2.32銆1锛氬弻渚у亣璁撅紝鎷掔粷鍖哄煙鍦ㄤ袱杈硅屼笖涓よ竟瀵圭О锛屽湪棰樼洰闂綘鈥濇槸鍚︾浉绛夛紵鈥濈殑...
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绛旓細鍙嶇潃鏌ャ備緥濡傦細98%鐨勭疆淇″尯闂寸畻Z锛1-0.98=0.02锛0.02/2=0.01; 1-0.01=0.9900锛涙煡姝ｆ鍒嗗竷琛紝鍦ㄩ偅涓鍫嗗洓浣嶅皬鏁扮殑鍊奸噷鎵惧埌涓0.9900鏈鎺ヨ繎鐨勫硷紝姣斿0.9901瀵瑰簲鐨勬槸2.33锛屾墍浠98%瀵瑰簲鐨Z缁熻閲鏄2.33鎴2.32銆1锛氬弻渚у亣璁撅紝鎷掔粷鍖哄煙鍦ㄤ袱杈硅屼笖涓よ竟瀵圭О锛屽湪棰樼洰闂綘鈥濇槸鍚︾浉绛夛紵鈥濈殑...
绛旓細鍙嶇潃鏌ャ備緥濡傦細98%鐨勭疆淇″尯闂寸畻Z锛1-0.98=0.02锛0.02/2=0.01; 1-0.01=0.9900锛涙煡姝ｆ鍒嗗竷琛紝鍦ㄩ偅涓鍫嗗洓浣嶅皬鏁扮殑鍊奸噷鎵惧埌涓0.9900鏈鎺ヨ繎鐨勫硷紝姣斿0.9901瀵瑰簲鐨勬槸2.33锛屾墍浠98%瀵瑰簲鐨Z缁熻閲鏄2.33鎴2.32銆1锛氬弻渚у亣璁撅紝鎷掔粷鍖哄煙鍦ㄤ袱杈硅屼笖涓よ竟瀵圭О锛屽湪棰樼洰闂綘鈥濇槸鍚︾浉绛夛紵鈥濈殑...
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