The second type of inferential statistics we discussed earlier was
hypothesis testing. This is sometimes called statistical testing as
well. In point estimation and in constructing a confidence interval
we had no expectations about the values we calculated, where as in
hypothesis testing we have formed some expectation about the
population parameter.
Example
Our hypothesis is that tree mortality after a
particular forest fire will be greater then 60%. In other words
average tree mortality > 60%.
Once our notion of the population parameter has been developed,
we can write two contradictory hypotheses. The first is the research
hypothesis, which in our case is that the mean tree mortality > 60%.
The second hypothesis is called the null hypothesis, and is the
opposite of our research hypothesis. In our example the null
hypothesis would be stated as the mean tree mortality is less than
or equal to 60%. |