if we take Eevee for example.
Eevee has base numbers for attack, defence and stamina, which u can find at http://pokemongo.gamepress.gg/pokemon/133
on top of those stats every eevee spawned will have a random IV-value between 0-15 added on top of the base value
So an Eevees attack stat could for instance differ between 114+0 and 114+15
and the goes for defence and stamina
