各位大神，小弟刚刚接触MATLAB空间计量工具箱，拜托大家帮忙解释一下莫兰指数检验的语句，包括函数以及赋值等等谢谢！！！

if nargin ~= 3
error('Wrong # of arguments to moran');
end;

[n k] = size(x);

% standardize the weight matrix
W = normw(W);

% do ols to get residuals
b = inv(x'*x)*x'*y;
e = y - x*b;
epe = e'*e;
mi = (e'*W*e)/epe;
M = eye(n) - x*(inv(x'*x))*x';
tmw = trace(M*W);

meani = tmw/(n-k);
vari =  trace((M*W)*(M*W')) + trace((M*W)*(M*W)) + tmw*tmw;
vari = vari/((n-k)*(n-k+2));
vari = vari - meani*meani;
mis = (mi-meani)/sqrt(vari);
prob = norm_prb(mis);

result.meth = 'moran';
result.nobs = n;
result.nvar = k;
result.morani = mi;
result.istat  = mis;
result.imean  = meani;
result.ivar   = vari;
result.prob   = prob;