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Apr
26
comment 'Level' still seems periodic after Season Decomposition
A couple of points to consider: (1) the range of "level" is about $0.05$ (and the daily fluctuation even smaller) compared with $0.25$ for "season1" and (2) you you might take averages of level for individual hours (ignoring days) to see if there is a much of a pattern. My guess is that the real daily seasonal pattern changed very slightly from beginning to end (especially in the final $8$ days) and this is causing some of the apparent pattern in "level"
Apr
26
comment Filter only names of Cities from datasets
Not a Cross Validated question. How would you know that Alert might be a geographical name?
Apr
26
comment Estimator of true probability — understanding margin of error for very small probability
It looks like it. Note that $\tilde{p}$ is slightly different to $\hat{p}$
Apr
26
comment Estimator of true probability — understanding margin of error for very small probability
The issue is the line $\displaystyle s_p = \sqrt{ \frac {p \, (1-p) } {n} } \le \sqrt{ \frac {0.5 \times 0.5 } {n} } = \frac {1}{2 \, \sqrt{n}}$ related to the title of the article Checking whether a coin is fair. If instead $p$ is close to $0$ or $1$, then $s_p$ will be much smaller. You might want to read the Wikipedia article Binomial proportion confidence interval which has some other approaches
Apr
25
comment What transformation should I use for a bimodal distribution?
@M.Beausoleil - in that case you really do not want to remove the bimodality, as it will reduce the discrimination of your analysis
Apr
24
comment Distribution of sum of squared normals, scalar form
Consider en.wikipedia.org/wiki/Noncentral_chi-squared_distribution
Apr
20
comment Making sense of Binominal GLM model
Perhaps this is telling you that a polynomial fit is not a good idea
Apr
20
comment Adding Normal Distributions
Your "standard formula" for $Z$ assumes independence between scores on the two tests. Is that true in your example?
Apr
20
comment Convergence in distribution of the following sequence of random variables
If it converges, then it converges to a distribution with point probabilities at $0$ and $1$, and which has an expectation of $\frac{\alpha}{ \alpha + \beta}$, so that gives you something to aim for
Apr
12
comment For a standard normal distribution, are p-values calculated using a $\Phi(-Z)$ or $\Phi(Z)$?
$\left|\dfrac{X-\mu}{\sigma}\right|$ will be non-negative, with the consequence that $2\Phi\left(\left|\dfrac{X-\mu}{\sigma}\right| \right) \ge 1$ so is unlikely to give a probability
Apr
11
comment unbiased estimate for household size
Note that if a village had half its households size $2$ and half size $6$ (so three-quarters of the inhabitants of the village lived in households size $6$), and you asked everybody in the village (e.g. stopping them in the street) then the average response would be $5$, while if you knocked at each door and asked the person opening the door, the average response would be $4$
Apr
4
comment Why do a density plot and a rug plot seem to disagree?
@RickHenderson: I added a chart with a narrower bandwidth and manual jitter
Apr
4
comment In statistics, should I assume $\log$ to mean $\log_{10}$ or the natural logarithm $\ln$?
ISO 31-11 seems to specify $\ln$ for $\log_e$, and leave an unadorned $\log$ undefined
Apr
4
comment In statistics, should I assume $\log$ to mean $\log_{10}$ or the natural logarithm $\ln$?
Since the graphs on pages 6 and 7 of Gale's paper show the original units on a log scale, and the calculations are aimed at the slope of a log-log relationship, i.e. $b$ in the expression $\log(N_r ) = a + b \log(r)$ which corresponds to $N_r=Ar^b$, it makes no practical difference in this case
Apr
1
comment Is this the solution to the p-value problem?
@Glen_b: Sorry - I missed the tag and my only excuse was that it was still March in my time zone when I read the message. whuber: The never-existent "Journal of the American Statistical Society" apparently gets half a million hits, and there is probably an interesting study in patterns of when it has been cited as such in research papers
Mar
31
comment Is this the solution to the p-value problem?
You do realise that this American Statistical Society is not a real organisation? (It was the name of the American Statistical Association from November 1839 to February 1840, but that hardly counts.) STOP is a joke
Mar
22
comment What are the most misused statistics terms that we should care to correct?
@ttnphns: some of us write generalised with an s
Mar
15
comment Difference between gaussian and lognormal
I cannot see any reason to expect a simple solution
Mar
9
comment Does the theory fit the given data?
I suspect the number of degrees of freedom is less than $3$ given the calculation of MLEs
Mar
9
comment Does the theory fit the given data?
Given the MLEs (which do not quite add up to $1$ due to rounding), the expected number type O should be $353 \times 0.580^2$