Bayesian probability: The lighthouse problem

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The discussion revolves around solving a homework problem related to Bayesian probability, specifically the lighthouse problem. The user is struggling with questions 2 and 3, having correctly approached question 1 using a formula for distance. For question 2, they initially apply Bayes' theorem but are advised that it is unnecessary because the problem states that pulses are emitted at "random azimuths," indicating a uniform distribution for θ_k. The user is encouraged to proceed with this understanding to continue solving the problem.
Niles
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Homework Statement


Hi all.

Please take a look at this problem: http://web.gps.caltech.edu/classes/ge193/practicals/practical3/Lighthouse.pdf

I am stuck at question 2 and 3. For question 1 I get the following:

<br /> d_k = \beta \tan(\theta_k)+\alpha.<br />

For question 2 and 3, I know I have to use Bayes' sentence for probability density functions (PDF's), so for question 2 I get:

<br /> p(\theta_k\,\, |\,\, \alpha, \beta) = \frac{p(\alpha,\beta\,\,|\,\,\theta_k)\pi^{-1}}{C},<br />

where C is some constant that normalizes the PDF and I have assumed that the prior probability on \theta_k is \pi^{-1} (I was told to do this).

Could you guys tell me, what the next step is?

Thanks in advance.


Niles.
 
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You're not supposed to use Bayes' theorem for #2. The answer to #2 is given by the statement that the pulses are emitted at "random azimuths". This presumably means that \theta_k is uniformly distributed between 0 and 2\pi.
 
Thanks! I'll keep working on it from here.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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