Pigheadedness a sign in recent changes (13)
I believe the answer is:
intransigence
'pigheadedness' is the definition.
(intransigence is a kind of pigheadedness)
'a sign in recent changes' is the wordplay.
'changes' indicates an anagram.
'a'+'sign'+'in'+'recent'='asigninrecent'
'asigninrecent' with letters rearranged gives 'INTRANSIGENCE'.
(Other definitions for intransigence that I've seen before include "lack of flexibility" , "Stubborn refusal to compromise" , "uncompromising attitude" , "pigheadedness" , "Refusal to budge" .)