Measuring Usability: Quantitative Usability, Statistics and Six-Sigma

Questions

The following questions have the tag Unusual Event associated with them. The number of users that have also tagged the question ' Unusual Event ' is in parenthesis.

On a police sergeants exam, the historical mean scored was 80 with a standard deviation of 20. Four . . . ( 4 )

A woman wrote to DearAbby and claimed that she gave birth 308 days after a visit from her husband, w. . . ( 3 )

Having obtained the z score and then derived the percentage... what does the percentage tell you?. . . ( 5 )

How unusual is this event (Z-Score)? A department store, on average, has daily sales of $28,. . . ( 6 )