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seen Dec 29 '11 at 3:49
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Nov
3
awarded  Yearling
Oct
2
awarded  Necromancer
Dec
18
comment How can I calculate a sample size for a ranked list of items across a population?
Perhaps, my answer to "Sample size for a variable number of answers" is relevant.
Dec
7
answered Are those two models equals?
Dec
7
answered Application of Hidden Markov Model to CRM
Dec
1
comment Explaining two-tailed tests
@chl I agree. However, for a person who is just being introduced to statistical ideas, re-writing the null for a one-tailed test may be a distraction when the focus is on how and why things change with respect to interpretation of the p-value.
Dec
1
revised Explaining two-tailed tests
fixed phrasing
Dec
1
answered Explaining two-tailed tests
Nov
30
comment Sample size for a variable number of answers
@CarlBenson For a normal distribution the z-value associated with a 95% confidence interval is 1.96. See the wiki link (en.wikipedia.org/wiki/1.96) for an explanation. Let me know if the link does not help and I will add further details to my answer.
Nov
30
answered Expected number of unseen cards when drawing $2n$ cards from a deck of size $n$
Nov
30
comment What happens if a survival curve doesn't reach 0.5?
@whuber Shouldn't the question be phrased as: "Does this mean that you can't estimate the median?".
Nov
30
revised Sample size for a variable number of answers
added 1 characters in body
Nov
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revised Sample size for a variable number of answers
added 1138 characters in body
Nov
30
comment Sample size for a variable number of answers
How did you get to 364?
Nov
30
awarded  Nice Answer
Nov
30
revised Sample size for a variable number of answers
added 273 characters in body
Nov
30
comment Sample size for a variable number of answers
@whuber Oh, I know. At the very least the above approach will get the OP started with something. One can compute margin of errors associated with the probability estimates and use that to compute required sample sizes. For $K=2$ the above collapses to the well known polling problem for which sample sizes are computed using margin of error. I am a bit lazy to actually look at MLE estimates and associated margin of errors!
Nov
30
answered Sample size for a variable number of answers
Nov
29
answered Tobit model explanation
Nov
29
comment We're trying to analyze which monsters drop what in an MMO
Logic stays the same. If you observe that two monsters $n$ and $n'$ do not drop the $m^\text{th}$ object then the probability of that happening is: $(1-p_{nm}) (1-p_{n'm})$ Include this probability as well in the likelihood function and maximize the likelihood function to estimate $p_{nm}, p_{n'm}$. You can also get confidence intervals for your estimates via maximum likelihood theory.