Muscle tension in the head region has been associated with tension headaches. Therefore, a physician reasoned that if the muscle tension could be reduced, perhaps the headaches would decrease or go away altogether. They design an experiment in which nine participants with tension headaches participate. The participants keep the logs of number of headaches experience during a two week baseline period. Then they are trained to lower their muscle tension in the head region, using a biofeedback device. For this experiment, the biofeedback device is connected to the frontalis muscle, a muscle in the forehead region. The device tells the participant the amount of tension in the muscle to which it is attached ( in this case, frontalis) and helps them achieve low tension levels. After six weeks of training, during which the participants have become successful at maintaining low frontalis muscle tension, They again keep a two week log of the number of headaches experience. The following are the number of headaches recorded during each two week period.
participant #
1
2
3
4
5
6
7
8
9
# headaches before training
17
13
6
5
5
10
8
6
7
# headaches after training
2
7
2
3
6
2
1
0
2
what is the null and alternative hypotheses?
what is the mean and standard deviation of each group?
clear indication of the hypothesis test being conducted and obtained statistic?
What is the results and conclusion?
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