Global null hypotheses

Statistically, the null hypothesis is Ho = the phenomenon (say, global warming) has no adverse impact. If we reject Ho and adopt a precautionary posture but in reality there was no adverse impact, we would have made a type 1 error. Not taking any corrective action and later finding out that there is an adverse impact would amount to a costly type 11 error. 

In the case of the test on the global significance of the regression, the null hypothesis is to be rejected, meaning that the residual sum of squares should be as small as possible. Whereas tabulated values are typically of the order of a few units, the calculated values should amount up to a few hundreds if not thousands, before the model can be considered as a potentially good model. 

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