INTERNAL COMBUSTION ENGINE CONDITION DETERMINATION APPARATUS, INTERNAL COMBUSTION ENGINE CONDITION DETERMINATION SYSTEM, AND DATA ANALYZING APPARATUS

A CPU calculates probability models by inputting input variables to a neural network. Next, the CPU determines whether a maximum value among the calculated probability models is larger than an upper limit value of a permissible range. When the maximum value is larger than the upper limit value of the permissible range, the CPU calculates a difference between the maximum value and a first reference value within the permissible range, and subtracts the difference from all the probability models. Then, the CPU calculates a probability of misfire in each cylinder by inputting each of the calculated probability models to a softmax function of mapping.