Question: A therapist treating clients for communication apprehension (fear of public speaking) assessed the effectiveness of the treatment by giving her clients a standard test at the beginning and at the end of treatment. The difference between the two scores was an indication of change. Here are the scores (a negative score indicates improvement).

If the treatment produced no effect, the change score would b 0, so assume that u = 0. Test the null hypothesis ( a= .05, directional). Did the treatment significantly reduce communication apprehension?