# Thread: Bernoulli trials

1. ## Bernoulli trials

a series of n Bernoulli trials is to be observed as data for testing $H_{0} : p = \frac{1}{2}$ versus $H_{1} : p > \frac{1}{2}$.
suppose that the null hypothese will be rejected only if k, the observed number of successes equals n.
for what value of p will the probability of making a Type II error equal 0.20?

2. Originally Posted by wik_chick88
a series of n Bernoulli trials is to be observed as data for testing $H_{0} : p = \frac{1}{2}$ versus $H_{1} : p > \frac{1}{2}$.
suppose that the null hypothese will be rejected only if k, the observed number of successes equals n.
for what value of p will the probability of making a Type II error equal 0.20?
You are being asked to find $p$ such that the probability $pr(k=n)=0.2$, where $pr(k=N)=b(N,n,p)$, so $pr(k=n)=b(n,n,p)=p^n$

CB

3. well u dont know k or n, so does that mean $p = \sqrt[n]{0.2}$, depending on what n is?

4. Yes.

CB

5. and thats the final answer?

6. Originally Posted by wik_chick88
and thats the final answer?
Why do you ask?

CB

7. just because the question is "for what VALUE of p..."
i guess it doesnt give u any more information anyway
thanks so much!