Why is the valuation of Oriental Fortune different from that of Tian Tian Fund, even the net value?

The intraday valuation system is to estimate the real-time net worth of an open-end fund according to the real-time stock quotation by using a set of specific algorithms of developers. It is not easy to estimate the net value of the fund. The fund's position portfolio is only published once every quarter, and the changes between quarters are unknown. Using the position portfolio of last quarter to estimate the net value must be a hundred thousand miles away. As for the use of advanced data mining technology, it is not impossible to match possible positions by comparing the daily net value of the fund with the stock price of the whole market on that day, but the accuracy seems to be difficult to guarantee.