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2d
comment Statistical Significance
If you are going to use the future perfect then perhaps you should move it out of the indicative, e.g. to "would have been rejected". You may also need to say the the "1%" represents the probability of erroneously rejecting the null hypothesis when it is in fact true, so "5%" involves that possibility and more.
Jun
19
comment What can we say about population mean from a sample size of 1?
This seems to give confidence intervals covering the mean with probability about $95\%$ when $\sigma \approx | \mu | \gt 0$ but with much higher probabilities otherwise. If $\mu = 0$ then clearly the probability is $100\%$ as the confidence intervals always contain $0$.
Jun
14
awarded  distributions
Jun
13
comment Percentile vs quantile vs quartile
A deeper question is whether quantiles etc. are intervals or points.
Jun
12
comment Estimating median survival times from Kaplan-Meier plot inspection
The data might show you that 16 out of 29 of the "mutation present" cases survived more than 4000 days (or whatever the numbers are), which is over 10 years. How would you work out the median from this?
Jun
11
comment Why is a symmetric distribution sufficient for the sample mean and variance to be uncorrelated?
@Glen_b: I am well aware that zero correlation does not imply independence. In fact my two bullet points were designed to show this difference. By the way, looking at your deleted answer, I thought about the Cauchy example in your second half and so said "if they have a correlation", while your first half deals with the "only if" point which my mine did not (the question seemed confused about this); so you might think about undeleting it.
Jun
10
comment Correlation coefficient is very small
Visually the relationship looks very weak on the right-hand side and if the regression line had been horizontal (something like $y=4$) I would not have been surprised
May
27
awarded  Nice Answer
May
25
comment Standard Error of the ratio of Binomial variates
$Y$ has a positive probability of being $0$ (so too does $X$) which is going to cause issues with $\frac {X-Y}{Y}$
May
17
comment Clarify probability solution re. birthdays
Remember that (in some countries at least) births on Saturday and Sunday are less common than on other days because doctors like not working at weekends.
May
17
comment Combine several days of time series into one
Yes you can, though whether a simple linear regression would be meaningful is another matter (e.g. if you were measuring tiredness, there might be a cyclical pattern)
May
12
comment Poker and the Birthday Problem
You can make order matter in your poker hands and have $\dfrac{52!}{47!}$ possible hands, i.e. $5!$ as many. You could easily adjust the rest of your analysis to fit this. But this option to choose whether to make order matter or not does not work so well with sampling with replacement especially if you want to use counting arguments.
May
10
comment Should I use A/B testing to find evidence that click-through rate has changed over four months?
I would have thought the rate was $35/100$. You can certainly do something like what you are suggesting, but I would not all it A/B testing, which I would have thought meant showing different ads to different people in the same time period and comparing response rates
May
3
comment Stationarity after differencing
If $\beta_1$ is a non-zero constant then $E[x_t]$ is increasing with $t$, so the original process is not constant in mean.
May
3
answered Stationarity after differencing
May
2
answered Training an SVM and performing cross validation
Apr
14
comment Why small values produce undulating densities when ploting logarithm of a loguniform prior (in R)?
If I try x <- 100^runif(1000000); plot(density(log(x))) then I get something which looks sensible between $0$ and about $4.6 \approx \log_e(100)$, so what did you run to get that oscillation?
Apr
10
comment Roll a 6-sided die until the total $\geq M$. Mean amount by which $M$ is exceeded?
I suspect that $M=300$ could be read as "very large $M$" as I believe that $M=301$ or $M=999$ would give almost exactly the same result. What I would do is find the distribution of the sum minus $M$.
Apr
9
comment Is there a name for this sort of plot? Is there any reason not to use it?
Difficult to find the $5$th percentile of $9$ observations. I think I would call what you are describing as a band chart: this is one (in fact two) looking at daily high and low temperature across the year in London.
Apr
8
comment Basic stats question - How to tell if my data distribution is symmetric
$-70,-63,-56,-49,-42,-35,-28,-21,-14,-7,0,1,4,9,16,25,36,49,64,81,100$ is deliberately not symmetric (uniform in the lower half but not in the upper half) and a box plot would put the median (equal to the mean) nearer the upper quartile than the lower quartile but also nearer the minimum than the maximum.