, ▁these ▁criteria ▁can ▁not ▁be ▁met ▁even ▁though ▁perfect ▁timing ▁is ▁applied ▁since ▁re actions ▁of ▁the ▁dog ▁and ▁effect iveness ▁of ▁the ▁method ▁depends ▁on ▁several ▁different ▁factors ▁such ▁as ▁the ▁willing ness , ▁strength ▁and ▁motiv ation ▁of ▁the ▁handler , ▁as ▁well ▁as ▁his / her ▁prof ic iency . ▁In ▁addition ▁to ▁that , ▁the ▁visibility ▁of ▁the ▁administrator ▁and , ▁thus , ▁of ▁the ▁pun ishment ▁is ▁another ▁important ▁factor ▁influen cing ▁the ▁efficiency ▁of ▁the ▁pin ch ▁col lar ▁because ▁the ▁dog ▁directly ▁links ▁the ▁pun ishment ▁with ▁its ▁owner . ▁Therefore ▁this ▁method ▁does ▁not ▁satisfy ▁the ▁‘ ‘ p un ishment ▁criteria ’ ’ ▁at ▁all . ▁The ▁qu itting ▁signal ▁on ▁the ▁other ▁hand ▁requires ▁criteria , ▁such ▁as ▁good ▁timing ▁and ▁struct ured ▁training ▁procedure , ▁on ▁account ▁of ▁complete ▁condition ing ▁to ▁achieve ▁effective ▁results . ▁Even ▁if ▁these ▁criteria ▁are ▁met , ▁the ▁person ality ▁trait ▁of ▁the ▁dog ▁is ▁another ▁factor , ▁which ▁influ ences ▁the ▁efficiency ▁of ▁the ▁signal ." ▁ ▁Sch al ke ▁et ▁al . ▁study ▁( 2 0 0 7 ) ▁Sch al ke ▁et ▁al . ▁conducted ▁a ▁ 7 - month ▁study ▁to ▁investigate ▁the ▁effect ▁of ▁shock ▁coll ars ▁on ▁stress ▁parameters , ▁in ▁a ▁series ▁of ▁different ▁training ▁situations . ▁Heart ▁rate ▁and ▁sal iva ▁cort is ol ▁were ▁used ▁to ▁determine ▁the ▁stress ▁levels ▁in ▁three ▁groups ▁of ▁dogs . ▁Group ▁A ▁received ▁the ▁electric ▁shock ▁when ▁they ▁touched ▁the