P-Values and Significance Levels
	Definitions:                       Observe          Hypothesize MI Does Make a Difference         0+           H+ MI Does Not Make a Difference       0-           H- P-Value:      P (O+/H-)    --  false-positive rate, often .05 or .01              --  aka Type 1 or alpha error Beta:           P (0-/H+)     --  false negative probability; for given n,                   lower alpha error rate => higher beta Sensitivity:  P (0+/H+)    --  true-positive rate, 1-beta or “power” Specificity:  P (O-/H-)     --  true-negative rate