The performance data is used to optimize {HEAD ~ the models} by adjusting {TAIL ~ element values} of constituent elements of the models 
The performance data is used to optimize { HEAD ~ the models } by adjusting { TAIL ~ element values } of constituent elements of the models
OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD REL REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH