Other forms of the null and alternate hypotheses

It is important to note that, whatever the outcome of the trial, both of these hypotheses cannot be correct. It is also true that one of them will always be correct. Again, we operationally define the term correct in this context in due course, but the point to note here is that  

The procedure of hypothesis testing allows us to determine which hypothesis is correct. 

A helpful way of remembering which hypothesis is which - that is, which form the null hypothesis takes and which the alternate hypothesis takes - is to conceptualize that the alternate hypothesis states what you are hoping to find and the null hypothesis states what you are not hoping to find. It must be emphasized here, however, that, although helpful, this conceptualization skates on very thin scientific ice As Turner (2007, p 101) noted  

In strict scientific terms, hope has no place in experimental research. The goal is to discover the truth, whatever it may be, and one should not start out hoping to find one particular outcome. In the real world, this ideologically pure stance is not common for many reasons (financial reasons being not the least of them). 

When we are hoping to demonstrate something different, however, these hypotheses take different forms. Consider the example of a trial called an equivalence trial. Equivalence trials are conducted to demonstrate that an investigational drug has therapeutic equivalence compared with a control treatment. Equivalence trials are also 

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