Questions tagged [two-sample]
The two-sample problem is: given samples X and Y from two distributions, test whether the two underlying distributions are the same. One of the most common classical nonparametric approach is the Kolmogorov-Smirnov test.
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Two sample similarity analysis for non-independent daily time series data
What two sample or other relevant statistical tests can be performed in R between two samples which are independent of each other, but the observations within each ...
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Doing a t-test on a normally distributed difference of two non normal distributions
I have two populations of donations (segment 2 people were subject to a different form):
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What difference between Mann-whintey U-test and Kolmogorov-Smirnov test on truncated log normal distributions?
I have two populations who have been exposed to two different websites that should bring them to donations: one with a progress bar that pushes them to give (B, segment 2) and the other not (A, ...
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T-test states difference of donation is significant when Z-test claims not, what method to use?
I have two populations who have been exposed to two different websites that should bring them to donations: one with a progress bar that pushes them to give (B, segment 2) and the other not (A, ...
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Why is the two-sample test giving me inconsistent results?
I am applying a two-sample t-test to determine whether we have software regressions on latency measurements.
Procedure
Run the test for build b1 and gather 60 latency measurements.
Run the test for ...
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Why am I observing non-uniformly distributed (negatively skewed) p-values for two-sample tests of mixture distributions when the null is true?
I am interested in generating Gaussian mixture distributions as the null distributions for a series of two-sample test simulations. It is a well established fact that p-values follow a uniform ...
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t-statistic varies widely when used for bootstrap sampling process
I have two samples of size 20 and I want to see if the difference between the geometric means is significant using two-sample t-statistic and bootstrap sampling.
Here is what I'm doing
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Testing for equal proportions when sample sizes are very small
Suppose I observe binary data for two samples (hopefully the notation below is obvious) and I wish to test the hypotheses:
$$H_0: p_1 = p_2$$
$$H_A: p_1 \neq p_2$$
I know there is a $z$-test for doing ...
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what is the difference between a two-sample t-test and a paired t-test
While I was glancing at hypothesis tests, I saw paired and two-sample t-test but couldn't understand the difference. For the explanation of these two tests, I saw the following sentence
" Two-...
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Can I simulate a two-sample K-S test when I can't perform a one-sample test because a distribution parameter is unknown?
Let's say I have a signal which I want to test for normality. I know that the mean from the theoretical distribution is zero, but it has an undetermined (unknown) variance. If I knew mean and variance ...
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R function for weighted two-sample t-test **with Welch-adjusted t statistic**?
I'm conducting a hypothesis test for the difference between two groups. The file dat1 contains all observations of measure for ...
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Determine distribution of a new test statistic
Question from my course project:
Suppose we are conducting a two-arm trial. For the control group, there are $n_c$ patients, and their outcome is denoted by X, which has distribution $N(\mu_{c},\sigma^...
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Two-sample test + paired/independent samples
This might be an easy question but I got lost in my thinking so thank you for clarifying that for me. So I have some troubles with understanding the ideas of two-sample tests in addition to paired and ...
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The mean of natural log of some data
I have the following data in natural log:
N = [0.929, -1.745, 1.677, 0.701, 0.128]
O = [2.233, -2.513, 1.204, 1.938, 2.533]
I want to calculate the mean ratio of ...
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Confused about Two Sample Proportion Tests - am I performing this correctly?
I am dealing with an advertising dataset that includes hundreds of advertisements, how many clicks each ad receives, whether the amount of clicks received is considered "high" or "low&...
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