Statistics might be described as the study of data in the presence of variation. Two different values in statistics are considered the same if they represent reasonable variation. For example, if we flip a coin 10 times, it would not be all that unusual to get 60% heads. So, we would not consider 60% heads in 10 flips to be any significant deviation from the 50% heads we expect. However, notice if we flipped a coin 10,000 times and received 60% heads, we would likely suspect the coin is not fair (i.e., does not result in heads 50% of the time). This is the key concept in studying inferential statistics, and a major idea to understand in this course.

In the Stent experiment, 20% of the treatment group had strokes; whereas, 12% of the control group had strokes. Do you believe the data show a real difference between the groups? Make certain toconsider the experiment, the sample size, and what you read in the book. Support your conclusion.

Also, something very interesting happened here as patients in the treatment group (those who had the stent) seemed to have a higher rate of stroke. This leads to an interesting new study with a new hypothesis about this particular brand of stent. What would that hypothesis be?