stata考试复习题库

例2-1从某单位1999年的职工体检资料中获得101名正常成年女子的血清总胆固醇（mmol/L）的测量结果如下，试编制频数分布表。2.354.213.325.354.174.132.784.263.584.344.844.414.783.953.923.583.664.283.263.502.704.614.752.913.914.594.192.684.524.913.183.684.833.873.953.914.154.554.803.414.123.955.084.533.923.585.353.843.603.514.063.073.554.233.574.833.523.844.503.964.503.274.523.194.593.753.984.134.263.633.875.713.304.734.175.133.784.573.803.933.783.994.484.284.065.265.253.985.033.513.863.023.704.333.293.254.154.364.953.003.26例题2-1(EX2-1.dta):.sumxVariable|ObsMeanStd.Dev.MinMax-------------+-----------------------------------------------------x|1014.029505.65921832.355.71.dir(max)-r(min)3.3600001.gengroup=int((x-2.30)/0.30)*0.30+2.3.tabgroupgroup|Freq.PercentCum.------------+-----------------------------------2.3|10.990.992.6|32.973.962.9|65.949.903.2|87.9217.823.5|1817.8235.643.8|1918.8154.464.1|1716.8371.294.4|1211.8883.174.7|98.9192.085|54.9597.035.3|21.9899.015.6|10.99100.00------------+-----------------------------------Total|101100.00例2-2用直接法计算例2-1某单位101名正常成年女子的血清总胆固醇的均数例2-3利用表2-1计算101名正常成年女子的血清总胆固醇均数。第2、3题了解即可，可以用最简单的方法求出：比如su，tabstat等例2-4某地5例微丝蚴血症患者治疗7年后用间接荧光抗体试验测得其抗体滴度倒数分别为10,20,40,40,160，求几何均数。例题2-4(EX2-4.dta):.meansxVariable|TypeObsMean[95%Conf.Interval]-------------+----------------------------------------------------------x|Arithmetic554-21.32307129.3231|Geometric534.822029.715194124.8121|Harmonic524.24242..------------------------------------------------------------------------Missingvaluesinconfidenceinterval(s)forharmonicmeanindicatethatconfidenceintervalisundefinedforcorrespondingvariable(s).ConsultReferenceManualfordetails.例2-569例类风湿关节炎（RA）患者血清EBV-VCA-lgG抗体滴度的分布见表2-5第(1)、(2)栏,求其平均抗体滴度。表2-569例RA患者血清EBV-VCA-lgG抗体测定结果抗体滴度人数f滴度倒数XlgXlgfX⑴⑵⑶⑷⑸1:101:201:401:801:1601:3201:6401:128043101011151421020408016032064012801.00001.30101.60211.90312.20412.50512.80623.10724.00003.903016.021019.031024.245137.576539.28686.2144合计69——150.2778例题2-5(EX2-5.dta):.meansx[fw=f]Variable|TypeObsMean[95%Conf.Interval]-------------+----------------------------------------------------------x|Arithmetic69280.8696212.754348.9851|Geometric69150.6411110.9425204.545|Harmonic6964.8458147.14289103.8391------------------------------------------------------------------------例2-67名病人患某病的潜伏期分别为2,3,4,5,6,9,16天，求其中位数。例题2-6(EX2-6.dta):.centilex--Binom.Interp.--Variable|ObsPercentileCentile[95%Conf.Interval]-------------+-------------------------------------------------------------x|75052.31428613.8例2-78名患者食物中毒的潜伏期分别为1,2,2,3,5,8,15,24小时，求其中位数。例题2-7(EX2-7.dta):.centilex--Binom.Interp.--Variable|ObsPercentileCentile[95%Conf.Interval]-------------+-------------------------------------------------------------x|85041.67517.925例2-8试计算表2-2某医院1123名产后出血孕妇人工流产次数的中位数。表2-2某医院1123名产后出血孕妇人流次数的分布人流次数产后出血人数累计频数累计频率（%）(1)(2)(3)(4)040240235.80133073265.18223296485.843118108296.35427110998.75511112099.73631123100.00合计1123——例题2-8(EX2-8.dta):.tabx[fw=f]x|Freq.PercentCum.------------+-----------------------------------0|40235.8035.801|33029.3965.182|23220.6685.843|11810.5196.354|272.4098.755|110.9899.736|30.27100.00------------+-----------------------------------Total|1123100.00.expandf(1116observationscreated).centilex--Binom.Interp.--Variable|ObsPercentileCentile[95%Conf.Interval]-------------+-------------------------------------------------------------x|112350111例2-10某地118名链球菌咽喉炎患者的潜伏期频数表见表2-5第(1)、(2)栏，试分别求中位数及第25、第75百分位数。表2-5118名链球菌咽喉炎患者的潜伏期天数人数，f累计频数累计频率（%）(1)(2)(3)(4)12～443.424～172117.836～325344.948～247765.360～189580.572～1210790.784～511294.996～411698.3≥1082118100.0例题2-10(EX2-10.dta):.tabx[fw=f]x|Freq.PercentCum.------------+-----------------------------------12|43.393.3924|1714.4117.8036|3227.1244.9248|2420.3465.2560|1815.2580.5172|1210.1790.6884|54.2494.9296|43.3998.31108|21.69100.00------------+-----------------------------------Total|118100.00例2-11试计算下面三组同龄男孩的身高(cm)均数和极差。甲组：9095100105110100cmX甲，1109020cmR甲；乙组：9698100102104100cmX乙，104968cmR乙；丙组：9699100101104100cmX丙，104968cmR丙。例2-13续例2-11，计算三组资料的标准差。例题2-11、2-13(EX2-11.dta):.sumx1-x3Variable|ObsMeanStd.Dev.MinMax-------------+-----------------------------------------------------x1|51007.90569490110x2|51003.16227896104x3|51002.91547696104例2-12续例2-10。已知25P=39.2，75P=67.7，计算118名链球菌咽喉炎患者潜伏期的四分位数间距。例题2-12(EX2-10.dta):Tabstatx[fw=f],st(iqr)直接求出四分位间距或者Tabstatx[fw=f],st(q)求出p25p50p75例2-15对例2-1，已计算出101名正常成年女子的血清总胆固醇均数4.06Xmmol/L，标准差0.654Smmol/L。试估计该单位：①正常女子血清总胆固醇在4.00mmol/L以下者占正常女子总人数的百分比；②在4.00~5.00mmol/L之间者占正常女子总人数的百分比；③在5.00mmol/L以上者各占正常女子总人数的百分比。例题2-15(EX2-1.dta):.sumxVariable|ObsMeanStd.Dev.MinMax-------------+-----------------------------------------------------x|1014.029505.65921832.355.71recodex(min/4=1)(4.01/5=2)(5.01/max=3),gen(group)tabgroup同时求出三个比例例2-16由例2-1资料估计正常女子血清总胆固醇的95%的参考值范围例题2-16(EX2-1.dta):.sumxVariable|ObsMeanStd.Dev.MinMax-------------+-----------------------------------------------------x|1014.029505.65921832.355.71.dir(mean)-1.96*r(sd)2.7374371.dir(mean)+.96*r(sd)4.6623546例3-1若某市1999年18岁男生身高服从均数为167.7cm，标准差为5.3cm的正态分布。从该正态分布N(167.7,5