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 2h comment Why is a moment called a moment? The concept is more like moment of inertia 1d comment What is zero mean and unit variance in terms of image data? Actually variance is the average of the squares of differences from the mean. Are you asking about "standardisation" or "rescaling"as preprocessing step? It is designed to avoid a single explanatory variable dominating the others just because it has a wide range of numerical values. Apr 27 answered Naive Bayes: Intuition behind the Evidence 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 revised Can this be analyzed with a parametric analysis? layout 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 25 answered What transformation should I use for a bimodal distribution? Apr 25 awarded Enlightened Apr 25 awarded Nice Answer Apr 24 comment Distribution of sum of squared normals, scalar form Apr 21 answered Percentage points for W in Worsley (1979, JASA) 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 5 answered Strong Vs Weak law of large numbers, (looking for Stat help and R simulation.)