System and method for monitoring process quality control

A method of modeling a relationship between a plurality of input parameters each having an variation range and an output parameter, said relationship having a plurality of possible states, the method comprising:

• discretizing said variation ranges into a plurality of sub-range vectors such that there is a plurality of sub-range vectors for each input parameter,
• building tuples of combinations of said sub-range vectors from respective ones of said input parameters,
• determining a statistical association between each tuple and values of said output parameter, and
• using said statistical association to model said relationship.

A system for monitoring a process having a plurality of input parameters, each parameter taking values within an input variation ranges, at least one output parameter taking values within an output variation range, the system having a plurality of possible operational states each associated with different parts of said output range, the system comprising:

• an input value recorder for recording a series of values of said input parameters,
• an output value recorder for recording a corresponding series of values of said at least one output parameter,
• a range divider for dividing said variation ranges of said input parameters into sub-range vectors,
• a tuple builder for building combinations of sub-range vectors from respective ones of said input parameters,
• a first associator for associating each tuple with statistically corresponding values of said at least one output parameter, and
• a second associator for associating each tuple with one of said possible operational states of said process, thereby to monitor said process in terms of said states.