Hello how to show the following:
Observations $(X_1,X_2,..,X_n,)$ are i.i.d. over $[0,2\pi)$ with density $f(x,\theta) = \exp[\theta_1\cos x + \theta_2 \sin x -c(\theta)]$ where $\theta =(\theta_1,\theta_2) \in R^2$
Find an expression for the Fisher information $I(\theta)$ involving integrals and show that it is positive definite for all $\theta \in R^2$
Thank you!