In the technical parameter group, the prime parameter is price and the parameter set is {TAIL ~ a set} of {HEAD ~ performance parameters}  
In the technical parameter group , the prime parameter is price and the parameter set is { TAIL ~ a set } of { HEAD ~ performance parameters }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH