设随机变量X与Y的分布律分别为：
\u8bbe\u968f\u673a\u53d8\u91cf(X,Y)\u7684\u5206\u5e03\u5f8b\u4e3aP{1/2<X<3/2,0<Y<4} =P\uff08X=1\uff0cY=1\uff09+P\uff08X=1\uff0cY=2\uff09+P\uff08X=1\uff0cY=3\uff09=1/4
P{1\u300aX\u300a2\uff0c3\u300aY\u300a4}= P\uff08X=1\uff0cY=3\uff09+P\uff08X=1\uff0cY=4\uff09+P\uff08X=2\uff0cY=3\uff09+P\uff08X=2\uff0cY=4\uff09=1/16+1/4=5/16
\u7531\u4e8e:P(X=0, Y=0)=P(X=1, Y=0)=P(X=0, Y=1)=P(X=1, Y=1)= 1/4.
P(Z=1)= P(X=1, Y=0)+ P(X=0, Y=1)+ P(X=1, Y=1)= 3/4.
P(Z=0) =:P(X=0, Y=0) =1/4..
Z\u7684\u5206\u5e03\u5f8b: P(Z=0)=1/4, P(Z=1) = 3/4.
P 1/9 1/9 1/9 2/9 2/9 2/9
Z=XY -1 0 1 2
P =P(0,-1) =P(0,0)+P(-1,1) =P(0,1)+P(1,0) =P(1,1)
=1/9 =3/9=1/3 =3/9=1/3 =2/9
绛旓細=1/9 =3/9=1/3 =3/9=1/3 =2/9
绛旓細P{1/2<X<3/2,0<Y<4} =P锛圶=1锛孻=1锛+P锛圶=1锛孻=2锛+P锛圶=1锛孻=3锛=1/4 P{1銆奨銆2锛3銆奩銆4}= P锛圶=1锛孻=3锛+P锛圶=1锛孻=4锛+P锛圶=2锛孻=3锛+P锛圶=2锛孻=4锛=1/16+1/4=5/16
绛旓細a+b=1-1/4-1/4=1/2 P{X=0|Y=0}=1/2琛ㄧず鍦╕=0鐨勬儏鍐典笅锛孹=0鐨勬鐜囦负1/2锛岄偅涔坅=1/4 鍒檅=1/4 渚嬪锛歑鐨勮竟缂樺垎甯 X -1 0 1 P 0.2 0.5 0.3 Z=X+Y鐨勫垎甯冨緥 Z -1 0 1 2 P 0 0.4 0.5 0.1
绛旓細2014-11-11 姒傜巼缁熻璁鹃殢鏈哄彉閲廥鐨勫垎甯冨緥涓篜(X=k)=1/2^k(k=... 13 2014-10-07 楂樻暟姒傜巼璁轰笌鏁扮悊缁熻闂,宸茬煡浜岀淮闅忔満鍙橀噺(X,Y)鐨勮仈鍚堝垎... 8 2013-06-25 姒傜巼璁轰笌鏁扮悊缁熻!璁鹃殢鏈哄彉閲廥鐨勫垎甯冨緥涓:X鍒嗗埆鏄-1,0,... 1 2019-03-27 姒傜巼缁熻璁鹃殢鏈哄彉閲廥鐨勫垎甯冨緥涓篜(X=k)=1/2^k(k...
绛旓細鍥犱负鍙湁杩欎袱缁勫彇鍊硷紝鍙互寰楀嚭Y=15-5X锛屾墍浠ョ浉鍏崇郴鏁颁负-1銆傚鏋滀竴瀹氳璁＄畻鐨勮瘽锛屽彲浠ュ弬鑰冧笅鍥惧垪鍑烘鐜囪〃骞惰绠楁湡鏈涖佹柟宸佸崗鏂瑰樊锛屾渶鍚庢眰鍑虹浉鍏崇郴鏁般
绛旓細鐢变簬鍒嗗竷寰涓悇涓鐜嘼ai涔嬪拰涓1锛屽洜姝=1/8銆傝仈鍚堝垎甯冨嚱鏁颁互浜岀淮鎯呭舰涓轰緥锛岃嫢锛圶锛孻锛夋槸浜岀淮闅忔満鍚戦噺锛寈銆亂鏄换鎰忎袱涓疄鏁帮紝鍒欑О浜屽厓鍑芥暟銆傝(X,Y)鏄簩缁撮殢鏈哄彉閲忥紝瀵逛簬浠绘剰瀹炴暟x,y锛屼簩鍏冨嚱鏁帮細F(x,y) = P{(X<=x) 浜 (Y<=y)} => P(X<=x, Y<=y)锛闅忔満鍙橀噺X鍜孻鐨鑱斿悎鍒嗗竷...
绛旓細鍗硔X=0锛Y=-1}锛汢锛庣浉浜掔嫭绔嬬殑浜嬩欢瀹氫箟涓轰粬浠氦浜嬩欢鐨勬鐜囩瓑浜庡悇鑷鐜囩殑涔樼Н锛岀敱浜庝氦浜嬩欢{X=0锛孻=-1}鐨勬鐜囦笉鐭ワ紝鎵浠ユ棤娉曞垽鏂紱C锛庝簰涓哄绔嬩簨浠舵槸鎸囧鍚屼竴涓牱鏈┖闂磋岃█杩欎袱涓簨浠舵槸瀵逛袱涓牱鏈┖闂磋岃█鐨勶紱D锛庢牴鎹畾涔夛紝涓鍙橀噺浜掍笉鐩稿叧锛屽垯{X=0}鍜寋Y=-1}娌℃湁鍏崇郴锛庢晠閫夛細D锛
绛旓細DX=E锛圶²锛-锛圗X锛²=0.25 EY=5脳0.5+10脳0.5=7.5 E锛圷²锛=5²脳0.5+10²脳0.5=62.5 DY=E锛圷²锛-锛圗Y锛²=6.25 E锛XY锛=1脳5脳0=1脳10脳0.5=2脳5脳0.5+2脳10脳0=10 鍥犱负cov锛圶锛孻锛-EX脳EY=-1.25 鎵浠ワ細P=cov锛...
绛旓細鐢变簬:P(X=0, Y=0)=P(X=1, Y=0)=P(X=0, Y=1)=P(X=1, Y=1)= 1/4.P(Z=1)= P(X=1, Y=0)+ P(X=0, Y=1)+ P(X=1, Y=1)= 3/4.P(Z=0) =:P(X=0, Y=0) =1/4..Z鐨勫垎甯冨緥: P(Z=0)=1/4, P(Z=1) = 3/4....
绛旓細閫氬父鎯呭喌涓嬶紝XY鐨鑱斿悎鍒嗗竷寰鍙互閫氳繃姹傝ВX,Y鐨勮竟缂樺垎甯冨拰鏉′欢鍒嗗竷鏉ュ緱鍒般 杩涗竴姝ユ潵璇达紝鍦ㄧ粺璁″鍜屾鐜囪涓紝杈圭紭鍒嗗竷鎸囩殑鏄湪澶氱淮闅忔満鍙橀噺涓煇涓殢鏈哄彉閲忕殑姒傜巼鍒嗗竷銆傞偅涔堬紝鎴戜滑鍙互閫氳繃鍔犲拰鎵鏈夊叾浠栭殢鏈哄彉閲忕殑缁撴灉鏉ヨ幏寰楄闅忔満鍙橀噺鐨勮竟缂樺垎甯冦傚湪杩欎釜闂涓紝濡傛灉鎴戜滑鎯宠寰楀埌X鐨杈圭紭鍒嗗竷锛屾垜浠彲浠ラ氳繃瀵...
