x=0.1/200*[1:200];
plot(x,statDev,'k.')
% p1 =       38.19  (-4.054, 80.43)
%        p2 =      -13.89  (-20.34, -7.431)
%        p3 =       1.562  (1.283, 1.842)
%        p4 =  -0.0006966  (-0.00395, 0.002557)
y=38.19*x.^3-13.89*x.^2+1.562*x.^1-0.0006966;
hold on
plot(x,y,'k');
xlabel('sigma');
ylabel('ͳ¼ÆÎó²î');