Hawk-Dove game

In behavioral ecology the Snowdrift game is bettern known as the Hawk-Dove game which models intraspecific competition. When competing for resources or mates hawks escalate conflicts while doves are conciliatory. If two doves meet they share the resource s and both get $R=s/2$ but when facing a hawk the dove takes flight ($S=0$) and the hawks gets the entire resource $T=s$. However, if two hawks meet they escalate the conflict until one is injured at a cost $i$ ($i>s$). Escalation thus yields on average $P=(s-i)/2$. Consequently it pays to escalate when facing a dove but the dove is better off when facing a hawk. It is important to note that hawk and dove may refers to behavioral patterns of a single individual which are adopted with a certain probability. Thus the Hawk-Dove game can be viewed as a mixed strategy game. Such Hawk-Dove interactions are equivalent to the Snowdrift game with $b=(s+i)/2$ and $c=s$.

Since the Hawk-Dove game is equivalent to the Snowdrift game the payoffs can be rescaled in an analogous way which again results in $R=1$,$P=0$, $T=1+r$ and $S=1-r$ with $r=2s/(s+i)$.