２こう分布ｐ - 経済統計練習帳

var x = new Array();
var d = new Array();
var f = new Array();
var point = new Array();
 
function sample(){
 
 
    d[0] = 1;
    d[1] = 1;
    for(s=1;s<101;s++){
    d[s]=d[s-1]*s;    
    }
 
    p = 0.5;
    q = 0.5;
 
    for(k=0;k<101;k++){
    x[k]=d[100]*Math.pow(p,k)*Math.pow(q,100-k)/(d[k] * d[100 - k]);
    }
 
    v1 = 0;
    for (k = 0; k < 101;k++ ){
    v1=v1+x[k]*(k-50)*(k-50);    
    }
 
 
 
 
        maxy = 0;
for (s = 0; s < 101;s++ ){
if(x[s]>maxy)maxy=x[s];    
}
 
 alert(v1);
 
 
    paint();
 
 
}
 
function paint(){
 
 var sub=new svgpaint();
 
str="<svg width=\"500\" height=\"500\">";
 
for(s=0;s<101;s++){
x1 = 500*x[s]/maxy;
str=str+sub.rect(5*s,500-x1,5,x1,"blue");
}
 
str=str+sub.line(0,0,0,500,4,"black");
str=str+sub.line(0,500,500,500,4,"black");
 
 
str=str+"</svg>";
 
$("#memo").html(str);      
 
 
}