In this lab, you will explore in detail the resistance of some of the summary measures you have studied in chapter 2. Specifically, you will see how the mean, median, quartiles, and standard deviation are affected by creating and removing outliers, and by changing the values of data points. In addition, you will be able to study the effects that these manipulations have on box-and-whisker plots and frequency histograms.
In the lab, a JAVA applet will provide graphical and numerical summaries of car theft data from the 50 states. In the applet, you will be asked to click and drag points. To do this, first imagine there is a horizontal axis through the center of the box-and-whisker plot. Think of this as the horizontal line that would result if the whiskers were extended into the box. When the position of the pointer on this axis corresponds to one of the car theft rates in the data set, the value of that car theft rate and the name of the state to which it belongs will appear to the right side, underneath the box-and-whisker plot. When the pointer is positioned over any such data point, you can click and drag that point to a new value.
To navigate through the lab, use the menu bar on the left side of this window, which will be available to you throughout the lab. Click "Applet" to open the applet for this lab. Once you open the applet, there will be specific step-by-step instructions found at the bottom of the applet window. Once you have completed the lab, you may be instructed to answer the summary questions. Even if you are not, have a look: they will be a good test of your understanding.