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.
Figure 1. Box plot of data from the MichelsonâMorley experiment. In descriptive statistics, a box plot or boxplot is a convenient way of graphically depicting groups of numerical data through their quartiles. Box plots may also have lines extending vertically from the boxes (whiskers) indicating variability outside the upper and lower quartiles, hence the terms box-and-whisker plot and box-and-whisker diagram.