Archive for April, 2007

Histogram as a mini-graph

Monday, April 30th, 2007

Average and median intend to characterize distributions with a single value. Often, this is not enough. If you want to understand data you have to look at it. Rafe has a nice idea how to do this in an information-dense way.

Mrs. Johnson’s piano class last year had eight students of varying ages pianoclass01, seven of them children and one older gentleman, Mr. Onaip, who provided the other students with an interesting perspective on music and life in general. This year, the age distribution is noticeably different pianoclass01, since Mr. Onaip has brought along two of his like-aged friends and his daughter, Allegro, who has just graduated from medical school.

It works in Excel, too.

How important it is to look at data in detail is demonstrated in the story of Stephen Jay Gould [in German].

Living in Pixelland

Sunday, April 15th, 2007

Every pixel is valuable in Pixelland. The graph below is still pixel-junk on Pixelland’s standards.

Altria_Sparkline_1

The parantheses waste 30 valuable pixels.

Altria_Sparkline_2

The vertical line costs 11 pixels.

Altria_Sparkline_3

Empty spaces also use pixels which is vital.

Altria_Sparkline_4

Font-width can be measured in pixels, too.

Altria_Sparkline_5