Hypothesis testing

Hypothesis testing is a formal process for statisticians and data scientists. The standard approach to hypothesis testing is to define an area of research, decide which variables are necessary to measure what is being studied, and then to set out two competing hypotheses. In order to avoid only looking at the data that confirms our biases, researchers will state their hypothesis clearly ahead of time. Statistics can then be used to confirm or refute this hypothesis, based on the data.

In order to help retain our visitors, designers go to work on a variation of our home page that uses all the latest techniques to keep the attention of our audience. We'd like to be sure that our effort isn't in vain, so we will look for an increase in dwell time on the new site.

Therefore, our research question is "does the new site cause the visitor's dwell time to increase"? We decide that this should be tested with reference to the mean dwell time. Now, we need to set out our two hypotheses...