Which "mean" to use and when? - Cross Validated
So we have arithmetic mean (AM), geometric mean (GM) and harmonic mean (HM). Their mathematical formulation is also well known along with their associated stereotypical …
What is implied by standard deviation being much larger than the …
What does it imply for standard deviation being more than twice the mean? Our data is timing data from event durations and so strictly positive. (Sometimes very small negatives show up …
Why is Standard Deviation preferred over Absolute Deviations …
Jan 7, 2025 · The mean is the number that minimizes the sum of squared deviations. Absolute mean deviation achieves point (1), and absolute median deviation achieves both points (1) …
Finding the Mean and Variance from PDF - Cross Validated
Jan 15, 2015 · If $\theta=4$ how to you find the mean and variance? My guess was to plug in $4$ of course and then integrate that function from $0$ to infinity. As for the variance I honestly …
mean - How do I calculate confidence intervals for a non-normal ...
You can just use a standard confidence interval for the mean: Bear in mind that when we calculate confidence intervals for the mean, we can appeal to the central limit theorem and use …
mean - "Averaging" variances - Cross Validated
May 6, 2017 · I need to obtain some sort of "average" among a list of variances, but have trouble coming up with a reasonable solution. There is an interesting discussion about the differences …
regression - When is R squared negative? - Cross Validated
This is because, without the benefit of an intercept, the regression could do worse than the sample mean in terms of tracking the dependent variable (i.e., the numerator could be greater …
How to calculate `mean` and `sd` of lognormal distribution based …
May 29, 2020 · Lognormal distribution as below: estimate meanlog 6.0515 sdlog 0.3703 How to calculate the mean and sd of this distribution?
What is the significance of 1 SD? - Cross Validated
Nov 2, 2024 · What do you mean by "the derivative at 1 SD is +- 1"? Derivative of what? If you mean of a density plot, then what distribution? The normal? Different distributions will have …
Should I use 'median' instead of 'mean' for nonparametric …
Jun 6, 2020 · The mean has a proper interpretation outside normal distributions, and it can have problems, such as its vulnerability to outliers (which in some applications is more of a problem …