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We have previously discussed the importance of estimating uncertainty in our measurements and incorporating it into data analysis 1. To know the extent to which we can generalize our observations, we ...

Central Limit Theorem: A sampling distribution of the mean is approximately normally distributed if the sample size is sufficiently large. This is true no matter what the population distribution is.

This paper presents the results of a limited investigation which brings into focus the difficulties encountered in developing exact distribution-free methods for stratified simple random sampling. It ...

When an experiment is reproduced we almost never obtain exactly the same results. Instead, repeated measurements span a range of values because of biological variability and precision limits of ...

In life and fatique testing, multi-censored samples arise when at various stages of a test, some of the survivors are withdrawn from further observation. Sample specimens which remain after each stage ...

Sometimes you can just look at the data and see the null hypothesis is clearly false. (For example, if a histogram shows that every observation is greater than the null hypothesis value). The methods ...