Consider the following model on panel data:
$$Y_{it}=\alpha+\frac{\beta_i}{\beta_i+\gamma} X_{1,it} + \frac{\gamma}{\beta_i+\gamma} X_{2,it},$$
where $i$ is a cross-sectional unit index and $t$ is time. Further, $Y_{it}>0$. What would be the best way to estimate the parameters of this model?