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Home Statistical Tests Means and Medians TwoSample tTest Large Sample Size  
See also: small sample size, distribution calculator, survey on statistical tests  
TwoSample tTest  Large SamplesWe define a new variable: the difference,
between the means and of the two samples. The mean of this variable d is . Its standard deviation is given by: which is also called the standard error. For large samples (n_{1},
n_{2}) the distribution of the differences d is approximately normal.
So we can apply the same methods as for the onesample
ttest for large samples, but now using the new variable d.


Home Statistical Tests Means and Medians TwoSample tTest Large Sample Size 