Power analyses and sample size calculations are important parts of many research projects. Often, before data are even collected, it is necessary to calculate and justify the required sample size for ...

Power analyses and sample size calculations are important parts of many research projects. Often, before data are even collected, it is necessary to calculate and justify the required sample size for ...

State the factors that affect power and what factors we have to specify to do a sample size calculation. Some notes on the behaviour of sample size calculations and power for unequal group sizes This ...

This relationship also applies to another statistic sometimes needed for sample size calculations, which relates to variation. Take the case of the pain trial, where we are trying to see whether a ...

It's used to calculate and refine projected risk ... in statistical analysis because it gives validity to your sample size. The assumptions you make when working with a small amount of data ...

Its sample size, subject to the calculation I described above. 2. Its pollster reliability rating. 3. Its recentness rating, as described in the FAQ. Note that “old” polls from the same ...

The recentness rating is still applied as described in the FAQ, and multiplied by the Effective Sample Size calculation to produce the final weighting. This method has one very interesting quality ...