I'm working on a problem for "Inferences about the difference between two population means for independent samples: sigma 1 & 2 unknown and unequal." The final value of "test statistic t" falls in the rejection region for 95% confidence interval, but falls in the nonrejection region for 99% confidence interval. Should I perform additional calculations before rejecting my null hypothesis?
What would be a good statistical approach to find manipulated test results? [more inside]
Statistics-filter: Two relatively (I think) simple statistics questions. [more inside]
Having run split tests on the e-commerce website at work, how do I extract meaningful conclusions from the raw data? [more inside]
How can an estimate of a health risk (eg 1 in 500) have a false positive? [more inside]
Is there a formula or process to determine how many questions should be on an exam? Given a test bank of "x" number of questions, what "y" number of randomly selected questions constitutes a valid sample? [more inside]
In science, what is the difference between a theory and a law? Why is something called a law rather than a theory?