This page introduces the different charts I drew from the Visitor Statistics

The charts are

• scattergraph: pehaps the simplest of all graphs on which we simply plot our values, in this case the number of visitors day by day
• bar chart: the bar chart is very similar to the scattergraph except that instead of points, dots or crosses, the values are drawn as bars starting at the horizontal axis
• histogram: a more advanced chart that takes relative values of the data into account
• ogive: a more than and less than chart. an ogive plots two curves: the cumulative data building from the lowest value to the maximum; and the cumulative data decreasing from the maximum to the lowest
• radar chart: a radar chart has this name because it looks like a radar screen. A radar chart effectively shows the high points of a distribution
• doughnut chart: a pie chart with a hole in the middle: each data point is allocated a place on the doughnut!
• logarithmic chart: in this case, we hvae plotted the [natural] logarithmic value of the visitors against the normal values of the dates
• output gap type chart: Economists use what's called an Output Gap Chart and this is equivalent to that. We take the average value of all of the data and then subtract that value one by one from each data value giving a positive, negative or zero value
• Z chart: a chart that comprises three curves that collectively form a shape that looks like the letter "Z": raw data, cumulative data, moving average data

To make our lives as simple as possible, I have put the file into Acrobat/PDF format: it should load more easily because of this and it will look better on screen and when printed out, too.

In addition to the charts, I have posted the raw data on the site, too: clearly, if you're simply looking at alternative ways of presenting the same information, the charts are enough by themselves. However, if you'd like to see and manipulate the data, go here: The visitor stats that these charts come from

If you would like to see what Microsoft Excel does in terms of deriving the basic statistics from a data series, have a look at this link, Descriptive statistics that Excel derived from the visitor data.

Duncan Williamson
3 November 2001