Lucy (Skillet song) Lucy (Skillet song) "Lucy" is the fifth single of the 2009 album "Awake" by the Christian rock band Skillet, and is the twelfth and final track on the album. John Cooper initially refrained from discussing the song's full meaning, stating that it has "a gist of regret where you wish you had done things differently" and "even though there's a specific story, it has a lot of interpretations that have kind of meant a lot to a lot of people already." In November 2010, at a concert at the Target Center in Minneapolis, Cooper revealed it is about a young
Differential item functioning Differential item functioning Differential item functioning (DIF) is a statistical characteristic of an item that shows the extent to which the item might be measuring different abilities for members of separate subgroups. Average item scores for subgroups having the same overall score on the test are compared to determine whether the item is measuring in essentially the same way for all subgroups. The presence of DIF requires review and judgment, and it does not necessarily indicate the presence of bias. DIF analysis provides an indication of unexpected behavior of items on a test. An item does not display DIF if