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1d
comment Is a confidence interval a prediction interval for the sample mean?
See stats.stackexchange.com/questions/16493/… for more
1d
comment Is a confidence interval a prediction interval for the sample mean?
That is not the standard definition of a $95\%$ confidence interval, which is more along the lines of applying the same methodology to repeated independent sample means with the same sample size, $95\%$ of the confidence intervals so constructed would include the population mean. I also have doubts about your description of the prediction interval, which does not seem to depend on the actual value of the sample mean observed. A difference is that the prediction interval takes account of the uncertainty of the next sample mean compared with the population mean, in addition to this sample's.
1d
comment What Ratio of Independent Distributions gives a Normal Distribution?
A rather special case is $X$ a standard normal, and $Y$ independently $\pm1$ each with probability $\frac12$, then $X$, $Y$ and $\frac{X}{Y}$ have the same mean and variance and $\frac{X}{Y}$ is normally distributed.
2d
revised How to obtain index of a vector?
code
Oct
27
comment What is a log-odds distribution?
It is possible that your model could produce arbitrarily large positive or negative results. These might not be interpretable in terms of a bounded range such as a probability, but could be interpretable as log-odds using the logit function and its inverse the logistic function.
Oct
18
comment Visualize a large binary matrix with instances and three classes
You can visualise an matrix for example using image but you might want to reorder the rows and columns first into clusters or something similar
Oct
18
comment How to quantify the importance of a win in soccer?
You would want to give it a rating similar to teams it was perceived to be as likely to win or lose against.
Oct
17
answered How to quantify the importance of a win in soccer?
Oct
17
comment Why doesn't runif generate the same result every time?
Or xkcd
Oct
17
comment Why doesn't runif generate the same result every time?
@ssdecontrol: See Dilbert
Oct
15
comment Variance in significance with interaction term
First note that there is no major difference in substance between $-0.017$ and $-0.019$ even if the latter gets a . Second, the interaction term says that the $-0.019$ becomes $-0.033$ when *Rule of Law is $+1$ and $-0.047$ when Rule of Law is $+2$ but $+0.009$ when Rule of Law is $-2$. Finally remember that this is a model and the world is more complicated: historically the rule of law is in part the result of competing property owners find a dispute resolution procedure which does not involve violence.
Oct
15
comment Variance in significance with interaction term
What is wrong with "The effect of NatRent is now the effect of NatRent when Rule of Law is zero"?
Oct
12
comment Fewest weight possible of the balls
This is a puzzle, not a statistics question. You can find the odd ball of $4$ in $2$ weighings (a) if you do not need to know whether the odd ball is heavier or lighter or (b) if you have a fifth ball you know is of standard weight you can use.
Oct
10
comment Definition of Parameters
Don't parameters just take you from a general case or a family of cases to a particular one? So a Gaussian distribution with $\mu=10$ and $\sigma^2=4$ is a particular case of Gaussian distributions, in the same way that a straight line with gradient $10$ and intercept $4$ is a particular case of straight lines.
Oct
2
answered R code to solve for probability of normal distributions?
Oct
2
comment R code to solve for probability of normal distributions?
stat.ethz.ch/R-manual/R-devel/library/stats/html/Normal.html
Oct
2
comment R code to solve for probability of normal distributions?
Try ?pnormand ?qnorm
Oct
2
comment How can I work out the standard deviation of a t-distribution?
Do you mean $\frac{\nu}{\nu-2}$ for $\nu \gt 2$?
Oct
2
comment What does O(t) correction mean?
en.wikipedia.org/wiki/Big_O_notation
Oct
1
comment Help! Stat test to compare groups
Even if you are able to distinguish the two countries, but remember that correlation is not causation (the "because of" in your hypothesis).