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 …
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 - Is it correct to use plus or minus symbol before standard ...
Apr 21, 2015 · I have represented standard deviation as "±SD" before in publications. But I like to have opinions on this. Is it appropriate to use the notation '±' with SD ? Or ...
Will the mean of a set of means always be the same as the mean …
Jan 13, 2015 · The above calculations also demonstrate that there is no general order between the mean of the means and the overall mean. In other words, the hypotheses "mean of means …
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 …
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 …
mean - Is Median Absolute Percentage Error useless? - Cross …
Nov 20, 2022 · I'm working on a project focused on pricing houses. Looking online I see a lot of works and companies providing the performances of their model using the median instead of …
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 …
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?
Finding mean when class sizes are unequal - Cross Validated
What will be the mean no. of days a student was absent? I am unable to understand since the class sizes are different. Update In both the first 2 answers, the authors have assumed …