X = [R1,Xt_1,Xt_2,Xt_3];
Y = y;
modelfun = @(1+exp(b(1)*(b(2)-b(3))*X(:,4)*(X(:,2)-X(:,1)*X(:,3)))).^(-1).*b(2)*X(:,2)+(1-(1+exp(b(1)*(b(2)-b(3))*X(:,4)*(X(:,2)-X(:,1)*X(:,3)))).^(-1)).*b(3)*X(:,2);
beta0=[-10, 0.5, 0.5];
mdl = NonLinearModel.fit(X,Y,modelfun,beta0);

2Â¥: Originally posted by dingd at 2015-03-06 09:42:43
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