Data values for the set of metrics for the field web sites can also be obtained from {HEAD ~ other publicly available information/sources} in the web, {TAIL ~ such a} from public ad placement keyword suggestion tools for search engines, by way of example 
Data values for the set of metrics for the field web sites can also be obtained from { HEAD ~ other publicly available information / sources } in the web , { TAIL ~ such a } from public ad placement keyword suggestion tools for search engines , by way of example
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH