概率分布与统计推断.ppt

（4）参数估计：估计出该刀具的均值为594，方差204，均值的0.95置信区间为[553.4962，634.5038]，方差的0.95置信区间为[179.2276，237.1329].[muhat,sigmahat,muci,sigmaci]=normfit(x)第94页,共95页，星期六，2024年，5月（5）假设检验已知刀具的寿命服从正态分布，现在方差未知的情况下，检验其均值m是否等于594.结果：h=0，sig=1，ci=[553.4962，634.5038].(1)布尔变量h=0,表示不拒绝零假设.说明提出的假设寿命均值594是合理的.(2)95%的置信区间为[553.5，634.5],它完全包括594,且精度很高.(3)p值为1,不能拒绝零假设.[h,p,ci]=ttest(x,594,0.05,0)第95页,共95页，星期六，2024年，5月mjd=3.58513.55233.35942.60030.40113.08053.04782.85482.09570.90570.39420.36140.19900.59073.59202.38912.35632.16341.40431.59711.65811.62541.43241.07802.32811.36171.32891.13600.83872.62452.46402.43132.23831.49131.52222.57132.53852.34561.61641.41492.08392.05111.85811.41421.90242.33182.29902.10611.58491.65441.67051.63781.44481.00092.31572.05612.02331.83031.36051.9302第62页,共95页，星期六，2024年，5月pp=543215432132145453214321543215453215432143521453214321543521等级杭州西湖5武汉东湖5青海湖3巢湖4滇池4鄱阳湖4太湖4洞庭湖5洪泽湖4阳澄湖4洪湖4湖北武湖4第63页,共95页，星期六，2024年，5月每股收益(元)每股净资产（元）每股现金流量净资产收益率（%）主营收入增长率（%）主营利润增长率（%）资产负债比率（%）海尔0.3965.6601.6507.2723.0946.2147.73海信0.3046.860-0.1304.54-4.5090.4052.79奥柯玛0.0151.6700.2300.885611.68-46.5978.85长虹0.0363.510-0.3301.040419.4626.5367.55苏泊尔0.2504.4960.1305.6135.9527.0527.47小天鹅0.2105.050-1.1604.3349.018.1759.75TCL0.0532.4830.1542.1412.23275.4665.73美的0.2205.1200.0405.0496.13172.0064.55美菱0.0725.195-0.7901.383113