Alpha Level

Alpha Level

The alpha level (α) is the criterion for how low a probability needs to be to count as "unlikely"; a probability of Type I error that we are willing to accept. A common alpha level is α = .05 or less, meaning we are willing to accept a 5% or less error rate for drawing the wrong conclusion about the DGP based on our data (i.e., the empty model is true but we rejected it).


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