Well the thing is that the roboadviser is not even intended to make particular security picks. It is only supposed to decide which broad areas to invest in and

Well the thing is that the roboadviser is not even intended to make particular security picks. It is only supposed to decide which broad areas to invest in and what percentage for each area. Thus, the roboadviser can say that for your particular risk profile you should have 60% stocks 40% bonds and within the stocks you should have 60% sp500, 20% foreign large cap ... etc. My point is this portfolio distribution stuff is not an exact science and there really isn't a right answer. There are some broad accepted guidelines, but they are rather broad and simple and you definitely do not need computers to follow them.