What is the difference between alternative hypothesis and null hypothesis?

The link has a very good explanation of what you're looking for.|||Typically, the null hypothesis corresponds to a general or default position. For example, the null hypothesis might be that there is no relationship between two measured phenomena,



The alternative hypothesis, usually stated at the same time as the null hypothesis asserts, a particular relationship between the phenomena. The alternative need not be the logical negation of the null hypothesis. It predicts the results from the experiment if the alternative hypothesis is true.



The above from: http://en.wikipedia.org/wiki/Null_hypoth鈥?/a>



More simply, the null hypothesis is that there is no connection, while the alternative hypothesis is that there is a specific connection. If you want to know more there is a good discussion at:



http://www.experiment-resources.com/null鈥?/a>



Amusing discussion at:



http://www.null-hypothesis.co.uk/science鈥?/a>