The 5% (.05) significance level is the widely accepted criterion for Null Hypothesis Significance Testing. Discuss...

The 5% (.05) significance level is the widely accepted criterion for Null Hypothesis Significance Testing.
1. Discuss some problems with using a strict cutoff to determine whether your findings were significant. Discuss how you can make sure that you are presenting your results more fairly/honestly. How can a confidence interval help with estimating the practical significance of your results?

Expert Solution

Suppose a researcher wanted to check the impure substance present in any particular type of drink. From previous studies it is given that population mean impurity is 1.75 mg. Now the researcher have colected data on 26 sample and found sample mean as 1.96 mg and sample standard deviation as 0.42 mg. Objective is to check weather sample observation contradicts the population observation.

This question can be answered by one sample t test

If the stated assumptions are satisfied then we can be sure of our results and conclusions.

For our example confidence interval gives us the range within which any random sample mean impurity will fall.

That is even if we take any random sample drink of same type then we are sure that atleast 95% of the times sample mean impurity will lie between (1.790, 2.129). Similarly, for 99% confidence interval.

orchestra answered 2 years ago

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