PTS Blog

Ganesh, a reader of my web site, asked whether I could make a chart like this one:

The series are shown as a fluctuating blue Value line and a steadily increasing red Limit line in the line chart below, but Ganesh wanted to color code regions in the chart, so that regions where the value exceeded [...]

In Using Pivot Table Data for a Chart with a Dual Category Axis, I showed how to make a Chart with a Dual Category Axis using a pivot table to properly arrange the source data. I generally prefer using a regular chart, because pivot charts are pretty inflexible when it comes to formatting. Unfortunately, a [...]

In Using Pivot Table Data for a Chart with a Dual Category Axis, I showed how to make a Chart with a Dual Category Axis using a pivot table to properly arrange the source data. I generally prefer using a regular chart, because pivot charts are pretty inflexible when it comes to formatting. Unfortunately, a [...]

Tony commented on the previous post, Chart with a Dual Category Axis, asking whether I’d use a pareto chart for this data. I commented that it almost was a pareto chart, since at least within each category the data is sorted from high to low. Then I got to thinking, if I put my data [...]

Through appropriate arrangement of your source data, you can give your chart a dual category axis. This approach works with chart types that have an “Category” type category (X) axis, that is. line charts, column charts, and bar charts. The chart below shows defect rates in several different components, which are grouped into a smaller [...]

A candlestick chart is used to show stock price performance, typically daily; a bar shows the daily change from the opening to closing price, with different colors for gaining and losing changes, and lines extend from the bar to the daily high and low.

I was recently asked how to apply different arbitrary colors to individual [...]

I was directed to the web site for UberBI after reading The Uber Art of Dashboards on the Dashboards by Example blog. I want to say a few words about this chart, a stacked pyramid, which is featured prominently on one of UberBI’s displays.

Stacked Pyramid Chart
I occasionally read the Dashboards by Example blog, although I [...]

Dynamic ranges (or “Names”) are commonly used to identify a range of the appropriate length, so that a chart will plot the right number of points. For example, you may want to plot year to date sales, without blanks for the months which are still in the future. The dynamic range uses COUNT or similar [...]

In my last post, Secondary Axes in Charts, I described an essay by Stephen Few in which he concluded that secondary axes provide no benefit to good infographics. I have come to the same conclusion myself: secondary axes are more likely to confuse and obscure the data, than to clarify relationships in the data.
In the [...]

Stephen Few of Perceptual Edge writes about primary and secondary axis scales in the March 2008 Visual Business Intelligence Newsletter.
In this month’s essay, entitled Dual-Scaled Axes in Graphs-Are They Ever the Best Solution?, Stephen asks
Is it ever appropriate to include two quantitative scales on a single axis (Y or X) of a graph? Do dual-scaled axes [...]

A commonly used chart type for statistical analysis is a Main Effects Plot. I won’t go into the statistics behind this chart type here, but I want to show how easy it can be to construct such a chart. For this example, suppose there are three main effects, designated X1, X2, and X3, and an experimental [...]

Last fall, Many Eyes posted a bubble chart to show US Beer Shipments by Supplier. They made the chart using a visualization technique they call the matrix chart, which essentially supplies a matrix of rows representing one parameter, columns representing another, and a graphic at each grid location representing some value. In this case, the columns [...]