How do you know if two samples come from the same distribution?

How do you know if two samples come from the same distribution?

In general, in more qualitative terms:

1. If the Z-statistic is less than 2, the two samples are the same.
2. If the Z-statistic is between 2.0 and 2.5, the two samples are marginally different.
3. If the Z-statistic is between 2.5 and 3.0, the two samples are significantly different.

Which test is used to test whether two samples are likely to derive from the same population?

The two-sample t-test (Snedecor and Cochran, 1989) is used to determine if two population means are equal.

Can you say that the two samples came from the same population?

Independent groups mean that the two samples taken are independent, that is, sample values selected from one population are not related in any way to sample values selected from the other population. Matched pairs consist of two samples that are dependent.

What statistical tests would you perform to assess if two sets of samples come from the same underlying distribution?

Assuming your sample values come from continuous distributions, I would suggest the Kolmogorov-Smirnov test. It can be used to test whether two samples come from different distributions (this is how I am interpreting your usage of population) based on their associated empirical distributions.

How to test if two samples come from the same distribution?

Tests if two samples come from the same continuous distribution, against the alternative that they do not come from the same distribution. Lilliefors test. Tests if a sample comes from a distribution in the normal family, against the alternative that it does not come from a normal distribution.

Can a statistical test tell if two samples are pulled?

This is because there could be minor differences in the distributions (meaning they are not identical), but so small that tests cannot really find the difference. Consider 2 distributions, the first is uniform from 0 to 1, the second is a mixture of 2 uniforms, so it is 1 between 0 and 0.999, and also 1 between 9.999 and 10 (0 elsewhere).

How to test if multiple samples are drawn from the same population?

Tests if multiple samples are all drawn from the same populations (or equivalently, from different populations with the same distribution), against the alternative that they are not all drawn from the same population. One-sample Kolmogorov-Smirnov test.

Which is the best hypothesis test for two samples?

Two-sample t -test. Tests if two independent samples come from normal distributions with unknown but equal (or, optionally, unequal) variances and the same mean, against the alternative that the means are unequal. One-sample chi-square variance test.