《正态分布与参考值》PPT课件.ppt

《《正态分布与参考值》PPT课件.ppt》由会员上传分享，免费在线阅读，更多相关内容在教育资源-天天文库。

1、正态分布与医学参考值范围normaldistribution&medicalreferencerange67.375.473.170.975.172.678.268.873.871.566.575.170.768.973.372.376.574.375.975.467.271.876.270.670.775.673.372.476.667.380.874.373.971.679.969.380.375.773.581.274.472.577.167.374.168.076.470.471.075.873.678.168.772.677.672.274.272.176.369.771.175.

2、773.572.778.372.577.268.274.272.376.570.571.283.773.775.874.772.669.566.076.177.780.583.164.175.176.377.865.275.072.778.871.171.872.976.171.275.272.979.573.975.273.179.581.874.581.674.5表某地108名正常成年女子血清总蛋白(g/L)含量组段⑴频数,f⑵组中数,X⑶f·X⑷=⑵⑶f·X2⑸=⑵⑶264.0～66.0～68.0～70.0～72.0～74.0～76.0～78.0～80.0～82.0～84.0合计2681

3、525231476210865.067.069.071.073.075.077.079.081.083.0－130.0402.0552.01065.01825.01725.01078.0553.0486.0166.07982.08450.026934.038088.075615.0133225.0129375.083006.043687.039366.013778.0591524.0表108名正常成年女子血清总蛋白(g/L)频数分布图*某地108名正常成年女子血清总蛋白（g/L）含量直方图红细胞数/(1012/L)图某地150名正常成年男子红细胞数（1012/L）频数分布图.0.1.2.302

4、46810xf(x).0.1.2.30246810xf(x)正态分布正态分布（normaldistribution）也叫高斯分布（Gaussiandistribution），是最常见、最重要的一种连续型分布。一、正态分布的数学形式二、标准正态分布三、曲线下面积四、正态性检验五、正态分布的应用xf(x)一.正态分布的数学形式xf(x)mf(X)=随机变量X的频数，称为概率密度函数(probabilitydensityfunction)=总体方差,=总体均值X~N(,)以X为横坐标，f(X)为纵坐标，绘制的曲线就是正态曲线(normalcurve)正态分布的特征xf(x)二.标准正态分

5、布(standardnormaldistribution)两个参数：m=0,s=1，记为N(0,1)xms=1u标准正态分布N(0,1)一般正态分布N(m,s)正态曲线下的面积分布有一定的规律。求其一区间的面积，可通过下面积分公式得到。概率是曲线下的面积!Xf(X)XXf(X)abXf(X)a-a0三.曲线下面积p466附表10-11-1.961.96-2.582.5868.27%95.00%99.00%曲线下面积分布规律N(0,1)mm-sm+sm-1.96sm+1.96sm-2.58sm+2.58s68.27%95.00%99.00%N(m,s2)例某地108名正常成年女子的血清总

6、蛋白(g/L)如下表，试估计该地正常女子血清总蛋白<68.0g/L，<78.0g/L，≥78.0g/L所占正常女子总人数的百分比。67.375.473.170.975.172.678.268.873.871.566.575.170.768.973.372.376.574.375.975.467.271.876.270.670.775.673.372.476.667.380.874.373.971.679.969.380.375.773.581.274.472.577.167.374.168.076.470.471.075.873.678.168.772.677.672.274.272.176.

7、369.771.175.773.572.778.372.577.268.274.272.376.570.571.283.773.775.874.772.669.566.076.177.780.583.164.175.176.377.865.275.072.778.871.171.872.976.171.275.272.979.573.975.273.179.581.874.581.674.5表某地