电大【实用卫生统计学】作业第二次答案参考小抄.doc

专业好文档实用卫生统计学行考册作业2答案一、 名词解释1、 统计表：统计表是以表格的形式列出统计指标，它是对资料进行统计描述时的一种常用手段。2、 抽样误差：在同一总体中随机抽取样本含量相同的若干样本时，样本指标之间的差异以及样本指标与总体指标的差异，称为抽样误差。3、 均数的抽样误差：在同一总体中随机抽取样本含量相同的若干样本时，样本指标之间的差异以及样本指标与总体指标的差异，称为抽样误差。统计学上，对于抽样过程中产生的同一总体中均数之间的差异称为均数的抽样误差。4、 检验水准：也称为显著性水准，符号为。是预先规定的概率值，通常取0.05，它是“是否拒绝H0的界限”。5、 检验效能：又称为把握度。它的含义是：当两总体确实有差别时，按规定的检验水准能够发现两总体间差别的能力。二、 填空题1、 标题；标目；线条；数字2、 符合逻辑、主次分明；横标目在表中作主语，纵标目作谓语，连贯在一起阅读可以组成一句完整而通顺的话。3、 参数估计；假设检验4、 准确度；精确度5、 个体差异；抽样误差；样本指标；总体指标；样本指标6、 t检验；Z检验；方差分析7、 I型错误；II型错误三、 选择题1、C 2、B 3、C 4、A 5、A 6、C 7、C 8、D 9、C 10、D四、简答题1、答：（1）绘制统计表的基本原则是：A、一张表必须且只能有一个中心；B、项目的排列要合理，充分运用表格纵横交叉的形式使之一目了然。（2）统计表与统计图式统计描述的重要工具，统计表有利于计算、分析和对比，统计图有利于直观分析。 2、答：I型错误：拒绝了实际上成立的H0 ，这类“弃真”的错误称为I型错误。 II型错误：接受了实际上不成立的H0 ，这类存伪的错误称为II型错误假设检验的注意事项：（1）假设检验的前提可比性 （2）选用的假设检验方法应符合其适用条件 （3）正确理解假设检验过程中样本均数与总体均数间的关系 （4）正确理解“差别有统计学意义”的含义3、答：（1）误差有：A、系统误差 B、随机测量误差 C、抽样误差（2）均数标准误是样本均数的标准差，它反映了样本均数之间的离散程度，也反映了均数抽样误差的大小。（3）见教材P69表5.5。4、答：见教材P70表5.35、答：（1）方差分析的基本思想是将总变异分解成两个或多个部分，除随机误差外，其余每个部分的变异可以由某因素的作用来解释，通过比较可能由某因素所致的变异与随机误差的均方，由F检验作出统计推断，从而了解该因素有无作用。（2）t检验与方差分析均是用来比较总体之间均数的差别。一般方差分析可用于多个样本均数的比较，而t检验一般仅用于两样本均数的比较。6、答：Z检验的适用条件：总体标准差未知，但样本含量n较大（n>50）或总体标准差已知时，用Z检验。t检验的适用条件：当总体标准差未知，样本n较小时（）方差分析的适用条件：A、各处理组来自正态总体 B、各样本是相互独立的随机样本 C、各处理组的总体方差相等，即方差齐性。五、计算题1、解：（1）是配对设计；是自身对照设计（2）可以用配对t检验；可以用秩和检验，不过若能判断差值是属于正态分布的宜选用配对t检验。（3）先求出每一个患者给药前和给药后的差值d，H0：，即给药前后病人血管流量相同H1：，即给药前后病人血管流量不相同，所以P<0.05，应拒绝零假设，说明给药前后病人血管流量不同，即该药有效果。2、解：（1）完全随机设计；（2）应满足方差齐性，即甲、乙两组总体方差应相等。（3）；，；，所以有，尚不能认为两样本的方差不等。（3）建立检验假设：拒绝H0，因此饮食对肠蠕动效果有差别。3、解：（1）存在错误：a、没有标题；b、不必要的线条太多；c、横标目应为医院（2）修改后的表格为甲乙两医院某年内外科住院病人统计情况医院 内科 外科甲医院 800 1200乙医院 750 1250Winger Tuivasa-Sheck, who scored two tries in the Kiwis' 20-18 semi-final win over England, has been passed fit after a lower-leg injury, while Slater has been named at full-back but is still recovering from a knee injury aggravated against USA.Both sides boast 100% records heading into the encounter but Australia have not conceded a try since Josh Charnley's effort in their first pool match against England on the opening day.Aussie winger Jarryd Hayne is the competition's top try scorer with nine, closely followed by Tuivasa-Sheck with eight.But it is recently named Rugby League International Federation player of the year Sonny Bill Williams who has attracted the most interest in the tournament so far.The Kiwi - with a tournament high 17 offloads - has the chance of becoming the first player to win the World Cup in both rugby league and rugby union after triumphing with the All Blacks in 2011."I'd give every award back in a heartbeat just to get across the line this weekend," said Williams.The (lack of) air up there Watch mCayman Islands-based Webb, the head of Fifa's anti-racism taskforce, is in London for the Football Association's 150th anniversary celebrations and will attend City's Premier League match at Chelsea on Sunday."I am going to be at the match tomorrow and I have asked to meet Yaya Toure," he told BBC Sport."For me it's about how he felt and I would like to speak to him first to find out what his experience was."Uefa has opened disciplinary proceedings against CSKA for the "racist behaviour of their fans" during City's 2-1 win.Michel Platini, president of European football's governing body, has also ordered an immediate investigation into the referee's actions.CSKA said they were "surprised and disappointed" by Toure's complaint. In a statement the Russian side added: "We found no racist insults from fans of CSKA." Baumgartner the disappointing news: Mission aborted.The supersonic descent could happen as early as Sunda.The weather plays an important role in this mission. Starting at the ground, conditions have to be very calm - winds less than 2 mph, with no precipitation or humidity and limited cloud cover. The balloon, with capsule attached, will move through the lower level of the atmosphere (the troposphere) where our day-to-day weather lives. It will climb higher than the tip of Mount Everest (5.5 miles/8.85 kilometers), drifting even higher than the cruising altitude of commercial airliners (5.6 miles/9.17 kilometers) and into the stratosphere. As he crosses the boundary layer (called the tropopause),e can expect a lot of turbulence.The balloon will slowly drift to the edge of space at 120,000 feet ( Then, I would assume, he will slowly step out onto something resembling an Olympic diving platform.They blew it in 2008 when they got caught cold in the final and they will not make the same mistake against the Kiwis in Manchester.Five years ago they cruised through to the final and so far history has repeated itself here - the last try they conceded was scored by England's Josh Charnley in the opening game of the tournament.That could be classed as a weakness, a team under-cooked - but I have been impressed by the Kangaroos' focus in their games since then.They have been concentrating on the sort of stuff that wins you tough, even contests - strong defence, especially on their own goal-line, completing sets and a good kick-chase. They've been great at all the unglamorous stuff that often goes unnoticed in the stands but not by your team-mates.It is as though their entire tournament has been preparation for the final.In Johnathan Thurston, Cooper Cronk, Cameron Smith and either Billy Slater or Greg Inglis at full-back they have a spine that is unmatched in rugby league. They have played in so many high-pressure games - a priceless asset going into Saturday.The Kiwis are a lot less experienced but winning a dramatic match like their semi-final against England will do wonders for their confidence.They defeated Australia in the Four Nations final in 2010 and the last World Cup, and know they can rise to the big occasion.