Shingles is caused by the varicella zoster virus (VZV), the same virus that causes chickenpox. After a person recovers from chickenpox, the virus stays dormant (inactive) in the body. For reasons that are not fully known, the virus can reactivate years later, causing shingles. Shingles is not caused by the same virus that causes genital herpes, a sexually transmitted disease.
And different software packages use all different sorts of formulas. Be careful to use the formula from your book when doing your homework! Additionally, the box-and-whisker plot may include a cross or an X marking the mean value of the data, in addition to the line inside the box that marks the median. The difference between the X and the median line can then be used as a measure of skew. Please don't ask me to explain skew.
A vertical line through the interior of the box is drawn at x = , the median. Boxplots are basically a way of graphing the five-number summary. The simplest type of boxplot has the form: Also plotted are vertical lines at the positions x = minimum value, and x = maximum value.