已知是的2倍，是的1.2倍，样本相关系数r等于（）。https://img-ph-mirror.nosdn.127.net/fv6f0_WzU-KFGLXEIJ3lfA==/6632465244979208413.pnghttps://img-ph-mirror.nosdn.127.net/QsyEt8M0EjQvXJ9MGpNsjw==/6632558703467572691.pnghttps://img-ph-mirror.nosdn.127.net/TGqAMAKGqkhUE0R8gEif2Q==/6632540011769901040.pnghttps://img-ph-mirror.nosdn.127.net/QsyEt8M0EjQvXJ9MGpNsjw==/6632558703467572691.png

设,有划分，则，分别为https://img-ph-mirror.nosdn.127.net/_kVuHX7nBFHlNfzR3AeTRQ==/6631704382934470362.pnghttps://img-ph-mirror.nosdn.127.net/4QRI30JkP7V6jj57tHynuQ==/6608641027026760798.pnghttps://img-ph-mirror.nosdn.127.net/orOIv8YcdU_h_lUOdGNFCg==/6608226511145727302.pnghttps://img-ph-mirror.nosdn.127.net/giAuaiFtJSeucb0heLidqQ==/6597538158612635068.pnghttps://img-ph-mirror.nosdn.127.net/x1gGO27o3MWmLN9driNajQ==/1045116588544232433.pnghttps://img-ph-mirror.nosdn.127.net/A4wrtpUR5BGSeNCmbq_OcA==/1383168035656711023.png

设随机变量具有对称的密度函数，即，为的分布函数，则对任意实数,.https://img-ph-mirror.nosdn.127.net/lEiAQJQKvY14Qo2qj0E1Aw==/1072982611321422975.pnghttps://img-ph-mirror.nosdn.127.net/9BNVrADIkYbX410xL65RVg==/6631230493421812375.pnghttps://img-ph-mirror.nosdn.127.net/055psK1qEelFN3vSsaG0zQ==/6599288581122298726.pnghttps://img-ph-mirror.nosdn.127.net/lEiAQJQKvY14Qo2qj0E1Aw==/1072982611321422975.pnghttps://img-ph-mirror.nosdn.127.net/5ISpkzigMMeRmCo4M1UdLQ==/6608183630190574284.pnghttps://img-ph-mirror.nosdn.127.net/DDNn9dWDdvU11YRbl_vFSg==/285697101462025554.png

设，n=1,2,...，则当时，依概率收敛到1。https://img-ph-mirror.nosdn.127.net/hZM0olij5nqNZIKK23DMOQ==/6630887445792453443.pnghttps://img-ph-mirror.nosdn.127.net/mEL1KYPaCfhCxvAqAqJDvw==/1438337131091693287.pnghttps://img-ph-mirror.nosdn.127.net/teFw9dWCjy4xgYnz-6BRCA==/6619337076142062534.png

设，则（为常数）的值．https://img-ph-mirror.nosdn.127.net/OCKSU6xXGRmrhqyAjxCsLQ==/6608185829214053227.pnghttps://img-ph-mirror.nosdn.127.net/JkqlqFql5XkrAZfdvWFndg==/6608888417143176694.pnghttps://img-ph-mirror.nosdn.127.net/twXY8ldkHYPX6F401pfEHA==/6597409515751723222.png