= Solution
Let $Y_{ij}$ be the number of ice creams in price category $i\in\{\mathrm{high},\mathrm{low},\mathrm{medium}\}$ and score category $j\in\{\mathrm{excellent},\mathrm{good},\mathrm{poor}\}$. The fitted <Poisson regression> assumes that the nine counts are <independent random variables> with
$$
Y_{ij}\sim\operatorname{Pois}(\mu_{ij}),
\qquad
\log\mu_{ij}=\alpha_i+\beta_j,
$$
where the <logarithmic link function> is used and excellent is the <reference level in a regression factor>, so $\beta_{\mathrm{excellent}}=0$. Equivalently,
$$
\mu_{ij}=r_i s_j,
\qquad r_i=e^{\alpha_i},\quad s_j=e^{\beta_j}.
$$
This is the <independence log-linear model for a two-way contingency table>: price and score have main effects but no interaction.
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