Organizing Data

If we conduct an experiment of some kind, and collect data, we may face the problem of having too much of a good thing.... The difficulty comes when we try to answer questions like:

How do we deal with large amounts of data? or,
What have we learned from examining the data?

Statistics is a discipline that can help us resolve problems like making sense out of too much data. But, while statistical tools can be used to bring insight and clarity to large amounts of information, if used inappropriately, they can also lead to confusing, even misleading interpretations.

To begin, let's look at the data in the applet to the right. The data represent scoring that is typical of how students in this class perform on the first exam. Move the vertical scrollbar up and down to examine the scores. From this simple observation, are you able to form an impression about how values in the array are concentrated?

As you can see, the 100 scores are unsorted. You may also have noticed that they range in value from 38 to 98. But, extremes rarely tell you much about trends in the data and even if you take time to examine the scores, the lack of order and the sheer number of values make it difficult to make sense out of what you are viewing.