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semidevil
Feb22-05, 05:20 PM
ok, i'm stil a bit lost...so tell me if this is right:

f_y(y;\theta) = \frac{2y}{\theta^2}, for 0 < y < \theta

find the MLE estimator for theta.

L(\theta) = 2yn\theta^{-2 \sum_1^n y_i .

is this even right to begin with?

then take the natural log

ln2yn + -2\sum_1^n y_i * ln\theta

take derivative

\frac {1}{2yn} -\frac{ 2 * \sum_1^n yi}{\theta}.


now how do I solve this in terms of theta? and after that, what do I do next?

this just doesnt look right

and I also need to find it using the method of moments, but I get \frac {y^4}{2\theta} after the integral...


and this one too...this looks too messy:

fy(y;\theta) = \frac{y^3e^{\frac{-y}{\theta}}}{6\theta^4}