一般来说,年龄越大的人的β脂蛋白的含量越大。现观察三组人,他们都是男性。第一组人的年龄在20到30岁之间,第二组人的年龄在30到40岁之间,第三组人的年龄在40到50岁之间。他们的β脂蛋白的测量值如下表,问这三组人的测量值是否符合人们的经验:年龄越大的人的β脂蛋白的含量越大?
1.首先在mathematica中算出一些必要的值,之后化为标准正态分布:
a = {}; Subscript[m, 1] = {260, 200, 240, 170, 270, 205, 190, 200, 250, 200}; Subscript[m, 2] = {310, 310, 190, 225, 170, 210, 280, 210, 280, 240}; Subscript[m, 3] = {320, 260, 360, 310, 270, 380, 240, 295, 260, 250}; t = Sort[Join[Subscript[m, 1], Subscript[m, 2], Subscript[m, 3]]]; Do[Subscript[b, i] = {}, {i, 1, 3}]; Do[Do[AppendTo[Subscript[b, i], Position[t, Subscript[m, i][[j]]]], {j, 1, Length[Subscript[m, i]]}], {i, 1, 3}]; Do[Subscript[t, i] = Table[Apply[Plus, Subscript[b, i][[j]]]/ Length[Subscript[b, i][[j]]], {j, 1, Length[Subscript[m, i]]}], {i, 1, 3}]; m = Split[t]; a = {}; For[i = 1, i <= Length[m], i++, If[Length[m[[i]]] > 1, AppendTo[a, Length[m[[i]]]] ]]; Print[a]; Do[Subscript[n, i] = Length[Subscript[t, i]], {i, 1, 3}]; Do[Subscript[R, i] = Apply[Plus, Subscript[t, i]][[1]], {i, 1, 3}]; Do[Subscript[w, i] = 2 \!\( \*UnderoverscriptBox[\(\[Sum]\), \(t = 1\), \(i\)] \*SubscriptBox[\(n\), \(t\)]\) - Subscript[n, i], {i, 1, 3}]; Do[Print[{Subscript[n, i], Subscript[R, i], Subscript[w, i]}], {i, 1, 3}] T = \!\( \*UnderoverscriptBox[\(\[Sum]\), \(i = 1\), \(3\)]\(( \*SubscriptBox[\(w\), \(i\)]* \*SubscriptBox[\(R\), \(i\)])\)\) n = \!\( \*UnderoverscriptBox[\(\[Sum]\), \(i = 1\), \(3\)] \*SubscriptBox[\(n\), \(i\)]\); ET = n^2 (n + 1)/2 Do[Subscript[k, i] = (a[[i]])^3 - a[[i]], {i, 1, Length[a]}]; DT = N[(n*(n^2 - 1) - \!\( \*UnderoverscriptBox[\(\[Sum]\), \(i = 1\), \(Length[a]\)] \*SubscriptBox[\(k\), \(i\)]\))*(\!\( \*UnderoverscriptBox[\(\[Sum]\), \(i = 1\), \(3\)]\( \*SubscriptBox[\(n\), \(i\)]* \*SubscriptBox[\(w\), \(i\)]* \*SubscriptBox[\(w\), \(i\)]\)\) - n^3)/(12 (n - 1)), 9] y = -Abs[(T - (ET))/Sqrt[(DT)]]
2.然后将算出的y值代入SAS程序中
data; p=probnorm(-1.768463653); put p=; run;
3.最后算出p值为0.038491711。
有道无术,术尚可进;有术无道,止于术也!