function results=GJRforecast(data,error);
[parameters, LL, ht, VCVrobust, VCV, scores, diagnostics] = tarch(data, 1, 1, 1, error);
results=parameters(1)+parameters(2)*data(end)^2+parameters(3)*(data(end)<0)*data(end)^2+parameters(4)*ht(end);