Question:Let $G$ be a finite abelian group and $X$ be a G-set. $K$ be a subgroup of $G$. let $i$ be a group homomorphism from $K$ to $G$ . I am looking for the map $$ i^{*} : H^{\alpha}_{G}(X,M) \rightarrow H^{i^{*}\alpha}_{K}(i^*X,i^*M).$$How can I compute this map $i^{*}$ for a constant Mackey functor $M$? Where $\alpha$ belongs to $RO(G)$ and $i^{*}X = X$ with $K$ - action induced by $G$. Note: For constant $G$- Mackecy fuctor $M$, $i^{*}M$ is $M$ as constant Mackey functor of $K$. Can anyone give some hint atleast for $X= point$.