Questions tagged [sample-size]
This tag is ambiguous. Use it when the question is about sample size and NONE of the following are more appropriate: [small-sample], [large-data], [statistical-power], [underdetermined], or [unbalanced-classes].
6 questions from the last 30 days
5
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Why does the p-value increase when I add more observations to my t-test?
I am comparing the means of two groups using an independent two-sample t-test in R. Initially, I had the following samples:
Group A: n = 15, mean = 52.3, sd = 4.8
Group B: n = 15, mean = 48.1, sd = 5....
- 51
2
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2
answers
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Sample size calculation for a single group and a single binary outcome measure
I have been asked to do a power calculation for a pre-post observational study. The researchers want me to calculate the sample size needed to detect a clinically meaningful number of clients ...
- 2,325
1
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0
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Sample size calculation for an outcome with multiple non-exclusive categorical responses
I've been asked to advise on a sample size calculation for a survey where the primary question of interest takes the following form:
Which of the following factors would influence your decision about ...
- 2,325