Recent content by ghotra

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    Expected Max of n Realizations of X: Mean + SD?

    Suppose I have a random variable X with known mean and standard deviation. After n realizations of X, what is the expected maximum of those n realizations? When n is very large, we know the mean of those realizations will be the mean of the distribution. Is the expected maximum simply the...
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    Joint Distribution of Changing Mean

    Interesting, I had wondered if that was okay to do...as the variance of X would then be the sum of the variances of the two normal distributions...and this is, in fact, sqrt(2). Could you explain how these are equivalent pictures? In general, I would like to consider a set of distributions...
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    Joint Distribution of Changing Mean

    Could you elaborate a bit more? I can confirm that the std deviation is indeed sqrt(2), however, I don't understand where the following formula comes from: E(X^2 | E(x) = m) = 1 + E(m^2) From the definition, \sigma_x^2 = E(x^2) - E(x)^2 = E(x^2) - m^2 Presumably, I stick your formula into...
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    Joint Distribution of Changing Mean

    Let X be a random variable with mean \mu and standard deviation 1. Let's add a twist. Suppose \mu is randomly distributed about 0 with standard deviation 1. At each iteration, we select a new \mu according to its distributuion. This mean is then used in the distribution for X. Then we pick...
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    What Defines a Microstate in Coin Tossing?

    Here are some thoughts. Please critque them. When speaking informally, we write the microstate as: (for distinct coins) HH HT TH TT However this just shorthand as marcusl implied. In physics, we cannot specify a microstate as above. We are treating the coins as independent. In...
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    What Defines a Microstate in Coin Tossing?

    You have implicitly assumed the coins are distinct. If the coins are identical, then there are only 3 microstates. This is exactly what Bose-Einstein statistics is about. From http://en.wikipedia.org/wiki/Satyendra_Nath_Bose: "Because photons are indistinguishable from each other, one...
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    What Defines a Microstate in Coin Tossing?

    There is no way that this is correct. The probability of getting a single head when tossing two real coins is always 1/2 and never 1/3. This is _interesting_. Even if I personally am unable to distinguish two coins from one another (thus, they are identical to me and to what I care about)...
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    What Defines a Microstate in Coin Tossing?

    ...any takers on this? Surely it isn't too difficult.
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    What Defines a Microstate in Coin Tossing?

    Maybe this didn't come through clearly. Why are the two coins distinct? I guess I was thinking that distinguishablity was a function of my interest. If I am only interested in the face of the coin, then all coins are identical. Obviously this line of thinking is wrong. I promise, I'm not...
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    What Defines a Microstate in Coin Tossing?

    I'm looking for some insight/clarification on the definition of a microstate. Consider two coins. Here are the possible outcomes: T T T H H T H H Now, I have assumed something: The coins are distinct. A better description of each microstate is: { (coin 1, T), (coin 2, T) }...
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    Integer Partition Restriction: Solving for q When k is Limited

    Wonderful! So, it doesn't appear that there is a closed form solution to this. However, the recurrence relation is quite nice, along with the Euler triangle. Thanks!
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    How Many Quantum States Can Four Bosons Have in a Harmonic Oscillator?

    Anyone? I know there are smart enough people here.
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    How Many Quantum States Can Four Bosons Have in a Harmonic Oscillator?

    Suppose I have 4 bosons in a one-dimensional harmonic oscillator potential and that the total energy is E_\text{tot} = 8 \hbar \omega. Recall, E_n = (n+1/2)\hbar\omega. Question: How many quantum states exist? (assume no spin degeneracy) After accounting for the ground state, we have 6...
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    Integer Partition Restriction: Solving for q When k is Limited

    Thanks. A quick look did not reveal any information on restricting the partitions as I discussed. Any other ideas?
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    Integer Partition Restriction: Solving for q When k is Limited

    Here is a much better statement of my question: How many integer solutions exist to the following equation: \sum_{i=1}^k n_i = N Let me call this number p(N,k). It is the number of partitions for N such that the partitions are restricted to be of order k or less. Example: N = 5 k = 3...
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