How do I combine standard deviations of two groups?
Oct 26, 2018 · This is the formula for the 'pooled standard deviation' in a pooled 2-sample t test. If we may have two samples from populations with different means, this is a reasonable estimate of the …
statistics - incremental computation of standard deviation ...
This is actually computationally efficient, because you just need to count the number of samples, the sum of the samples, and the sum of the squares of each sample. Once you need to "read" the …
How to calculate standard deviation when only mean of the data and ...
Sep 6, 2023 · see below the answer by : Graipher allows calculating the standard deviation from the mean and the number of samples. The mean of this distribution is given by μ=np , where n is the …
Standard deviation around mean rather than mode or median?
Feb 10, 2020 · 3 Why is standard deviation calculated from arithmetic mean and not from other measures of central tendency? I do get that standard deviation is to calculate dispersion, but why not …
Estimating the standard deviation by simply looking at a histogram
I understand that the standard deviation is a measure that is used to quantify the amount of variation or dispersion of a set of data values. How can I estimate the standard deviation by simply looking at the …
hypothesis testing - How to calculate standard deviation when only …
Dec 25, 2024 · How to calculate standard deviation when only mean of the data, sample size, and t-test is available? Ask Question Asked 1 year ago Modified 1 year ago
How to compute standard deviation of difference between two data …
0 There are better ways to estimate the standard deviation of the difference of two independent emperical datasets, when the probability distributions are unknown. You can use convolution, but a …
standard deviation - What is "the" correct way of calculating Cp/Cpk ...
Roth's suggestion was to simply use a calculated sample standard deviation based upon all the data regardless of the application because modern computing power eliminates the need to shortcut the …
standard deviation - How do I calculate the mean and SD of change …
Mar 9, 2022 · I need mean and standard deviation of change from baseline to follow-up for inclusion in a meta-analysis. Some papers present the findings as baseline mean, SD and follow-up mean, SD for …
standard deviation - How to calculate the error of percentages - Cross ...
Feb 20, 2019 · However, if what you're dealing with is a proportion (as in "73% of students passed the test, ie: a value between 0% and 100%), then you should calculate standard deviation from the …