# Tag Info

### How does reducing my alpha-threshold to 0.005 affect my required sample size?

As you wrote ".. there is no "simple" function mapping the old size to the new one .." --this is what I expected. However, following your suggestion and then plotting new against ...
Accepted

### How does reducing my alpha-threshold to 0.005 affect my required sample size?

There is very likely no "simple" function mapping the old sample size to the new one. The way to go about this would be to calculate the effect size detectable at the "old" sample ...
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1 vote

### Obtaining P value in LASSO regularized linear regression showing that the model is generalizable

It sounds like your supervisor wants to show p-values for coefficients similar to those that you would show for unpenalized regression. You can't just plug the selected predictors into an unpenalized ...
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### How do I interpret low subgroup interaction and high efficacy in only one group?

The Dangers of P-Value Hunts Peter already noted issues in your interpretation that I completely agree with (see my answer here, here, or here, which all show how meaningless $p$ values can become ...

### How do I interpret low subgroup interaction and high efficacy in only one group?

Welcome to CV. There are a few errors in your analysis, or, rather, in your interpretation of your analysis. First, you tested interpretation and found it was not significant. You concluded that the &...
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### Sample Size impact on Effect size

All things being equal, the major difference is the variation in the effect as a function of sample size. A very simple simulation in R shows this as the case. Here I simulate two groups who have the ...

### Sample Size impact on Effect size

The question is fully addressed by meta-analysis (see, e.g., Introduction to Meta‐Analysis by Borenstein et al.), which includes studying of how the effect size vary from one study to another. Indeed, ...
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### Report standard errors and exact p-value

The $p$ values are already a hairy subject, but I would trust them much less if there were no indicators of where that $p$ value came from. From my personal standpoint, you should always: List the ...

### Report standard errors and exact p-value

This is a style issue, and each journal has its own. However, if it was up to me, I'd require standard errors and make p values optional.
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### Sample Size impact on Effect size

When your sample size is small, there will be more sampling error attached to your effect size estimates and hence more uncertainty/wider confidence intervals. In that sense, I wouldn't say the effect ...
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### Sample Size impact on Effect size

As long as the sample is random, the estimate of the effect size is unbiased even in small samples. However, other things being equal, it will be less precise. It's still your best guess, but the ...
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### Never understood the concept of the p-value, it should be higher than 0.05

Sometimes it is easier to look at a visual representation to better understand the as extreme or more part of the definition of the p-value, or the p-value itself. Suppose you repeat an experiment ...
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### Never understood the concept of the p-value, it should be higher than 0.05

You wrote: If I understand correctly 'more extreme' are results in favour of the null hypothesis, because then a high p-value is in favour of it. this is just the opposite of the case. More extreme ...
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