In: Math
Let X1, X2, X3, X4 denote 4 independent observations from a distribution with density f(x;theta)=(1+theta)x^theta, if 0<=x<=1; 0 Otherwise.. What is the form of the LRT critical regoon for testing H0:theta =2 versus H1:theta=5
here,
Now, we are interested in testing the null hypothesis
against the alternative hypothesis
Now, to find the likelihood ratio, as defined above, we first
need to find
. Well, when the null hypothesis
is true,
can take on only one value, namely,
. Therefore:
We also need to find
in order to define the likelihood ratio. Well, when the alternate
hypothesis
is true,
can take on only one value, namely,
. Therefore:
Now, putting it all together to form the likelihood ratio, we get:
which simplifies to:
Now, the likelihood ratio test tells us to reject the null hypothesis when the likelihood ratio λ is small, that is, when:
where k is chosen to ensure that, in this case, α = 0.05. Well, by taking the natural log of both sides of the inequality, we can show that λ ≤ k is equivalent to:
Now, as
are independent observations, thus,
This distribution can be used to obtained the value of C at a given level of significance.